Dear collegues, we are seeing that global competition is increasingly shifting to science, technology and education.
Just recently, it seemed inconceivable that Russia could make not just a breakthrough but also a high-tech breakthrough in defence.
This was difficult, complex work.
Much had to be restored or started from scratch It was necessary to break new ground and find bold, unique solutions.
Nevertheless, this was done. It was done by our engineers, workers and scientists, including very young people that grew up with these projects.
Let me repeat that I know all the details of this large-scale effort and I am completely justified in saying,
for instance, that the development of the Avangard strategic hypersonic glide vehicle is tantamount to the launching of the world's first artificial satellite.
And not just in terms of enhancing the country's defence capability and security, although this is the primary goal,
but in influencing the consolidation of our scientific potential and the development of unique technological assets.
At one time, the nuclear defence project gave the country nuclear power.
The construction of a missile shield that started with the launch of the world's first artificial satellite allowed the country to begin peaceful space exploration.
Today, we need to use the personnel, knowledge, competences and materials we have acquired from developing the next generation of weapons
to produce the same kind of results for civilian applications.
We have yet to implement new ambitious scientific and technological programmes.
An Executive Order on genetic research has already been signed, and I propose launching a similar large-scale programme at the national level on artificial intelligence.
In the middle of the next decade, we should be among the leaders in these science and technology areas,
which, of course, will determine the future of the world and the future of Russia.
For more infomation >> BREAKING! Putin: Avangard Hypersonic Glider Launch Is Like Launching World's 1st Satellite - Duration: 2:04.-------------------------------------------
Why Apex's New Gun is BROKEN (Havoc Weapon Guide) - Duration: 5:32.
Why the HAVOC is INSANELY Good (New Energy Weapon)
Apex legends new gun is here and is crazy good!
Here is our review and gameplay on the new item added in the update.
(Apex legends gameplay)
-------------------------------------------
Jussie Smollet Is Now A Suspect - Duration: 0:41.
For more infomation >> Jussie Smollet Is Now A Suspect - Duration: 0:41. -------------------------------------------
What Brit Awards host Jack Whitehall said about one Liverpool star is absolutely SAVAGE - Duration: 3:13.
Striker Daniel Sturridge was joined by singing sensation Paloma Faith to present George Ezra with the British Male Solo Artist award earlier in the night
He then took a seat next to Alex Oxlade-Chamberlain - the other half of Little Mix singer Perrie Edwards - and it was he who felt the full Whitehall force
Whitehall proceeded to interview the Little Mix quartet later in the show where he tried to get them to put the boot in on Simon Cowell and their fierce critic Piers Morgan
The girls didn't play ball so comedian Whitehall instead turned his attentions to the footballers
"You girls have a wonderful time at the after-parties, nightclubs, kebab shops, or wherever you naughty Little Mixers get up to mischief," he told them
Whitehall then asked "have you booked your cars for after the show?" - before mocking Oxlade-Chamberlain for his injury woe
"Oxlade, are you going to be sharing an ambulance with Sturridge again?" Whitehall jibed, to which the England international gave a reluctant laugh
The midfielder snapped his knee ligaments in the Champions League semi-final last April
But his rehabilitation has gone so well he is back training on grass and doing ball work, prompting boss Jurgen Klopp to confirm he would be ready before the end of the season
Liverpool will refuse to push him and take every precaution to ensure the knee is 100 per cent right to avoid any further injury
But his return would offer a huge lift as the Reds go head-to-head with Manchester City during the Premier League run-in
The England midfielder was one of the key figures in Liverpool's form during the second half of last season and their run to the Champions League final
His relationship in providing assists for Mo Salah offered a real threat and his scoring from midfield was a key weapon that the Reds used to break down sides
The player himself is desperate to play a part this season, as Klopp's men look to end a 29-year Anfield wait for the title
Klopp hinted at an earlier return this month. Speaking about the midfielder he said: "He is close, very close
And in a really good way. "It looks really good, promising, close to return."
-------------------------------------------
Tuesday's Child Cameron is climbing to new heights - Duration: 1:17.
For more infomation >> Tuesday's Child Cameron is climbing to new heights - Duration: 1:17. -------------------------------------------
What is relative energy deficiency in sports? Trent Stellingwerff - Duration: 0:40.
RED's was established in 2014 during the IOC consensus as an extension of the
female athlete triad. And basically what it is, is when athletes do not consume
enough calories to meet the energetic demands of training. It affects both
health and performance outcomes. And it can be extreme or it can be very minor.
So it captures the idea that to optimise health, to optimise performance, athletes
need to consume enough calories.
-------------------------------------------
What Brit Awards host Jack Whitehall said about one Liverpool star is absolutely SAVAGE - Duration: 3:17.
Striker Daniel Sturridge was joined by singing sensation Paloma Faith to present George Ezra with the British Male Solo Artist award earlier in the night
He then took a seat next to Alex Oxlade-Chamberlain - the other half of Little Mix singer Perrie Edwards - and it was he who felt the full Whitehall force
Whitehall proceeded to interview the Little Mix quartet later in the show where he tried to get them to put the boot in on Simon Cowell and their fierce critic Piers Morgan
The girls didn't play ball so comedian Whitehall instead turned his attentions to the footballers
"You girls have a wonderful time at the after-parties, nightclubs, kebab shops, or wherever you naughty Little Mixers get up to mischief," he told them
Whitehall then asked "have you booked your cars for after the show?" - before mocking Oxlade-Chamberlain for his injury woe
"Oxlade, are you going to be sharing an ambulance with Sturridge again?" Whitehall jibed, to which the England international gave a reluctant laugh
The midfielder snapped his knee ligaments in the Champions League semi-final last April
But his rehabilitation has gone so well he is back training on grass and doing ball work, prompting boss Jurgen Klopp to confirm he would be ready before the end of the season
Liverpool will refuse to push him and take every precaution to ensure the knee is 100 per cent right to avoid any further injury
But his return would offer a huge lift as the Reds go head-to-head with Manchester City during the Premier League run-in
The England midfielder was one of the key figures in Liverpool's form during the second half of last season and their run to the Champions League final
His relationship in providing assists for Mo Salah offered a real threat and his scoring from midfield was a key weapon that the Reds used to break down sides
The player himself is desperate to play a part this season, as Klopp's men look to end a 29-year Anfield wait for the title
Klopp hinted at an earlier return this month. Speaking about the midfielder he said: "He is close, very close
And in a really good way. "It looks really good, promising, close to return."
-------------------------------------------
'General Hospital' Spoilers: Julian Tells Ava to Face Facts – Franco is the Killer - Duration: 5:43.
General Hospital spoilers show Ava Jerome (Maura West) heads to Julian Jerome (William deVry) for advice, possibly as she questions her future.
Ava wants to leave town with her current love Ryan Chamberlain (Jon Lindstrom), as she has no clue that he is the serial killer.
However, she can't bear to leave her child with Sonny Corinthos (Maurice Benard) behind.
Could Julian help her make a decision? General Hospital Spoilers: Ava Jerome Confides in Julian Jerome Ava begins to question what her future holds in upcoming GH episodes.
Ryan continues to push the idea of leaving town together, so they can get away before the serial killer mess explodes.
However, now he is keeping both Kevin Collins (also Jon Lindstrom) and Laura Spencer (Genie Francis) hostage, this complicates things.
General Hospital spoilers reveal Ava goes to her brother Julian Jerome for some advice. This may have to do with her future in Port Charles.
However, this also could be about Franco Baldwin (Roger Howarth) being accused of murder.
After all, Franco soon confesses to being the serial killer, even though he knows it's not true.
As Franco works with Jordan Ashford (Briana Nicole Henry) to flush the real killer out, Ava Jerome may find herself needing counsel.
After all, it seems that she and Julian argue over Franco as he questions her loyalty.
Could Julian Jerome help her come to terms with her future with "Kevin" – – or push her to see that Franco may be the killer?
GH Spoilers: Ryan Chamberlain Ties Up Loose Ends Things may fall apart bit by bit for Ryan as he works to tie up loose ends on General Hospital.
Now that Laura followed him to Ferncliff, she saw Kevin held captive.
But before she could process what she saw, Ryan Chamberlain drugged her.
Once she wakes and finds herself captive with Kevin, her husband has some explaining to do.
Obviously, Laura and Kevin work together to get out of confinement.
As Kevin is blind, this makes the task that much more difficult.
Laura needs to get home in order to protect Lulu Spencer (Emme Rylan), as she realizes that she is still in danger.
Now she knows Franco was telling her the truth about not being the killer.
However, as Ryan works to silence Laura and Kevin for good, he could lose everything. He wants to leave with Ava Jerome no matter what.
However, will this new Laura and Kevin situation ruin everything for him and lead to his downfall?
GH spoilers say he moves them to a more secure location but he must decide on a permanent solution soon.
General Hospital: Ava Jerome Continues to Stand By Franco? Ava may struggle with Franco's confession, much like Elizabeth Webber (Rebecca Herbst) is sure to do.
All Ava has wanted for the past few weeks has been to find the person who killed her daughter.
As more and more evidence points to Franco on GH, she could need some advice.
Or, she could need some advice on whether or not she should leave town with Ryan on General Hospital.
As it looks like Julian Jerome and Ava have somewhat of an argument before this bonding session, the two might make up as she seeks his help.
Ava may continue to stand by Franco, even if he does confess to all the crimes.
She knows he would never harm Kiki Jerome (Hayley Erin) but with the confession, plus Ryan and Julian pressuring her to realize Franco is the killer,
she may change her mind.
How long until Ava Jerome learns the awful truth about the man she's fallen for? When the facts are revealed, she will need Julian Jerome more than ever to support her.
-------------------------------------------
This Furla Tote Bag Is Over 50% Off and We Can't Stop Freaking Out - Live News 247 - Duration: 6:57.
Are our eyes deceiving us? Is this sale actually happening? Pinch Us so we wake up! Wait, actually, scratch that
If this is a dream, we want to stay in it forever. We won't be selfish though. We want everyone else to experience this with Us and take advantage of this sale before our alarm rings and we're snapped back to reality! This Ariana Leather Open Tote Bag is currently over half off
This is no teeny-tiny bag or wallet either; it's a full-sized tote! This sale is so good that two of the shades are already gone, so we need to act fast before the anti-magic words appear before us on our screen: sold out
This textured leather bag from is ultra luxurious. What else would we expect from the famous Italian brand? It features gold-tone styling, which is visible on the outside in the form of the brand's all-capitalized yet understated logo
This tote has double top handles which have an 8½-inch drop, making it long enough that we can wear it on our shoulder if we choose to, letting the bottom hit right around our hip
This bag doesn't have a zipper, but it still has a closure! A lobster clasp closure hides away inside of the tote, ready to clip on to the loop at the other side
We really like this lobster clasp because it's super easy to use for us, like an oversized necklace clasp, but it's harder to access for others than a zipper would be
It's subtle but still effective in keeping our belongings safe! On the inside of the tote is one big interior open pocket, along with an interior zip pocket! These pockets are coated with a textile lining
This tote has a 15-inch height and 12-inch length, so we can fit all of our essentials inside of it
A laptop, tablet, water bottle, change of shoes, charger, fact mist, book, kitten
. . okay, we won't keep a kitten in it, but it would totally fit! The zip pocket is nice and long, so we can also keep a healthy amount of belongings in there rather than trying to squeeze in two lipsticks instead of one
We also like this zip pocket for separating the items we're constantly reaching for, like our phone, keys, wallet and our kitten
Ah, caught kitten-handed again! This bag's size along with its clean and classic aesthetic make it extremely versatile and a go-to for travel
Luckily, it comes with an included dust bag, so if we need to pack it away for a plane ride or road trip, we can open it back up in another state or continent and find it in the same quality we left it in
No scruffs, scratches or stains here! The two colors currently available of this Ariana tote are different enough that we could get both
Just an idea! (One that we can't get out of our own heads.) Blue is a dark navy, capturing the tranquility of deep ocean waters or a late-night sky set aglow by countless stars
Navy can match with just about any color. We're certainly having trouble coming up with something it wouldn't work with
Avoiding wearing black and navy together is a super antiquated fashion rule and we're advocating for the pairing to come out to play! Vaniglia D is a neutral
It's a creamy beige, and as the same suggests in Italian, it takes on a rich vanilla ice cream color
We love vanilla ice cream because not only is it great on its own, but it lends itself so well to other toppings! The case is the same with this tote bag
We can pair it with darker shades a la chocolate syrup or any color of the rainbow a la sprinkles
Dessert break, anyone? This bag is perfect for commuters because of its functionality and size, but it's no clunky duffel bag or backpack
It's cute and sophisticated, so grab a pair of heels or booties and take it out on the town! And we mustn't forget to brag about how amazing of a deal we got on it
Now that's a fashion rule we refuse to give up. Check out more of our picks and deals here! This post is brought to you by Us Weekly's Shop With Us team
The Shop With Us team aims to highlight products and services our readers might find interesting and useful
Product and service selection, however, is in no way intended to constitute an endorsement by either Us Weekly or of any celebrity mentioned in the post
The Shop With Us team may receive products free of charge from manufacturers to test
In addition, Us Weekly receives compensation from the manufacturer of the products we write about when you click on a link and then purchase the product featured in an article
This does not drive our decision as to whether or not a product or service is featured or recommended
Shop With Us operates independently from advertising sales team. We welcome your feedback at ShopWithUs@
Happy shopping!
-------------------------------------------
Video: Tom Messner is looking for snow, sleet & freezing rain tonight. 2.20.19 - Duration: 3:54.
For more infomation >> Video: Tom Messner is looking for snow, sleet & freezing rain tonight. 2.20.19 - Duration: 3:54. -------------------------------------------
Arsenal news: Is this the clue Mesut Ozil is set to start in Europa League clash? - Duration: 2:08.
The German has struggled for regular playing time under Unai Emery this season. The pair have reportedly fallen out and Emery publicly called out Ozil earlier this season, suggesting he lacks the physicality for some games
Arsenal have struggled in recent weeks and fans have demanded Ozil plays in order to inject some creativity into the side
The Gunners are currently 1-0 down to BATE Borisov and they'll be looking to put things straight in the second leg at the Emirates tomorrow evening
And Ozil may have just hinted that he's starting the game. The 30-year-old posted a picture on Instagram of him posing with a group of his team-mates at training
The picture was accompanied by the caption 'We are the Arsenal' and some Gunners fans think Ozil could be set to feature against BATE
"Ozil go on the pitch n prove this stupid Emery wrong," one fan replied. While another added: "Hope to see you play, not only tomorrow, and provide killer passes
" Emery was asked extensively about Ozil's situation in his press conference earlier today
And the Spaniard admitted the playmaker's fate lies in his own hands. "Mostly, the key is his hand and he is working very well this week and I ask him in our conversations to be consistent," he said
"To be available for us training, when you can train with quality and consistency, it can help us with the best performance after in the games
"Now, this week is good for all the players, because we are in a big, important moment for the season and I look at him doing the training like we want
"I know he wants, but we need to be consistent and available in training and the matches without the injuries and without being sick
"Like that, we can find and see the best Mesut with us."
-------------------------------------------
Update Opinion Is the Green New Deal a Good Deal? The New York Times - Duration: 3:26.
Update Opinion Is the Green New Deal a Good Deal? The New York Times
Readers respond to columns by Bret Stephens, David Brooks and Ross Douthat.
To the Editor:
Re column, Feb. 16 :
Bret Stephens presents us with a fake binary choice. Either we gear up to fight climate change as if it were an alien invasion, placing capitalism in jeopardy, or we treat it as a real but manageable problem like global poverty, worthy of patient resolution. He urges us to make our peace with patient resolution.
The Green New Deals authors are doing us a favor by refusing to sugarcoat the need for fundamental change in the way we run our lives and fuel our economy. President Trumps defiant embrace of fossil fuels is an insult to common sense and global decency, but even President Barack Obamas policy reforms left gas guzzling cars on our roads, leaky homes throughout our towns and cities, and industries with their energy wasteful operations unchecked.
We have lost too much time pretending that climate change can be dealt with gradually, if at all. The Green New Deal rightly demands that we rise to the urgency of this challenge.
Philip WarburgNewton, Mass. The writer is a nonresident senior fellow at Boston Universitys Institute for Sustainable Energy.
To the Editor:
Re , by David Brooks column, Feb. 12 :
To suggest that a Green New Deal will evolve into a colossal government owned enterprise controlling most aspects of our economy and run by bureaucrats housed in Pentagon size offices is reactionary. This doesnt even happen in China anymore.
A Green New Deal will be enabled by the government just as it has enabled every modern high tech industry today: by funding military technology, the space program , by direct purchases supercomputers, semiconductors , by market subsidies wind power, solar power, electric vehicles , by technology transfer out of government labs and programs the internet, genomics, satellites , and the list goes on.
The government doesnt build things; private industries do, and they reap the commercial benefit. There are thousands of start up companies commercializing technologies in which the underlying research and development have been funded by the government, and there could be thousands more engaged in a Green New Deal if the government undertakes it.
John FairbornNewport Beach, Calif.
To the Editor:
Re column, Feb. 10 :
Before Ross Douthat dismisses carbon taxes as falling heavily on the working class, he should study the just introduced in Congress, to almost no fanfare.
It will reduce emissions more than the Paris agreement or President Barack Obamas Clean Power Plan; it requires no big government spending; and it already has generated bipartisan support.
The critical difference between this legislation and other carbon tax proposals is that all fees collected would be returned directly to American households each month. Most of the working class will actually come out ahead if this legislation passes.
Its a Green New Deal right under our noses!
Laura SchumacherSan Diego
To the Editor:
Ross Douthats patronizing take on the ambitions of the Green New Deal misses the most critical point: Scientists agree that humanity has a very short window in which to transform our systems of generating and using energy.
The alternative is stronger, more frequent hurricanes, droughts, floods, famines and wildfires, costing lives and livelihoods on a global scale.
If this doesnt call for great ambition, what does?
Sarah RichardsonNew York
-------------------------------------------
What Brit Awards host Jack Whitehall said about one Liverpool star is absolutely SAVAGE - Duration: 3:15.
Striker Daniel Sturridge was joined by singing sensation Paloma Faith to present George Ezra with the British Male Solo Artist award earlier in the night
He then took a seat next to Alex Oxlade-Chamberlain - the other half of Little Mix singer Perrie Edwards - and it was he who felt the full Whitehall force
Whitehall proceeded to interview the Little Mix quartet later in the show where he tried to get them to put the boot in on Simon Cowell and their fierce critic Piers Morgan
The girls didn't play ball so comedian Whitehall instead turned his attentions to the footballers
"You girls have a wonderful time at the after-parties, nightclubs, kebab shops, or wherever you naughty Little Mixers get up to mischief," he told them
Whitehall then asked "have you booked your cars for after the show?" - before mocking Oxlade-Chamberlain for his injury woe
"Oxlade, are you going to be sharing an ambulance with Sturridge again?" Whitehall jibed, to which the England international gave a reluctant laugh
The midfielder snapped his knee ligaments in the Champions League semi-final last April
But his rehabilitation has gone so well he is back training on grass and doing ball work, prompting boss Jurgen Klopp to confirm he would be ready before the end of the season
Liverpool will refuse to push him and take every precaution to ensure the knee is 100 per cent right to avoid any further injury
But his return would offer a huge lift as the Reds go head-to-head with Manchester City during the Premier League run-in
The England midfielder was one of the key figures in Liverpool's form during the second half of last season and their run to the Champions League final
His relationship in providing assists for Mo Salah offered a real threat and his scoring from midfield was a key weapon that the Reds used to break down sides
The player himself is desperate to play a part this season, as Klopp's men look to end a 29-year Anfield wait for the title
Klopp hinted at an earlier return this month. Speaking about the midfielder he said: "He is close, very close
And in a really good way. "It looks really good, promising, close to return."
-------------------------------------------
Opinion Is the Green New Deal a Good Deal? The New York Times - Duration: 3:17.
Opinion Is the Green New Deal a Good Deal? The New York Times
Readers respond to columns by Bret Stephens, David Brooks and Ross Douthat.
To the Editor:
Re column, Feb. 16 :
Bret Stephens presents us with a fake binary choice. Either we gear up to fight climate change as if it were an alien invasion, placing capitalism in jeopardy, or we treat it as a real but manageable problem like global poverty, worthy of patient resolution. He urges us to make our peace with patient resolution.
The Green New Deals authors are doing us a favor by refusing to sugarcoat the need for fundamental change in the way we run our lives and fuel our economy. President Trumps defiant embrace of fossil fuels is an insult to common sense and global decency, but even President Barack Obamas policy reforms left gas guzzling cars on our roads, leaky homes throughout our towns and cities, and industries with their energy wasteful operations unchecked.
We have lost too much time pretending that climate change can be dealt with gradually, if at all. The Green New Deal rightly demands that we rise to the urgency of this challenge.
Philip WarburgNewton, Mass. The writer is a nonresident senior fellow at Boston Universitys Institute for Sustainable Energy.
To the Editor:
Re , by David Brooks column, Feb. 12 :
To suggest that a Green New Deal will evolve into a colossal government owned enterprise controlling most aspects of our economy and run by bureaucrats housed in Pentagon size offices is reactionary. This doesnt even happen in China anymore.
A Green New Deal will be enabled by the government just as it has enabled every modern high tech industry today: by funding military technology, the space program , by direct purchases supercomputers, semiconductors , by market subsidies wind power, solar power, electric vehicles , by technology transfer out of government labs and programs the internet, genomics, satellites , and the list goes on.
The government doesnt build things; private industries do, and they reap the commercial benefit. There are thousands of start up companies commercializing technologies in which the underlying research and development have been funded by the government, and there could be thousands more engaged in a Green New Deal if the government undertakes it.
John FairbornNewport Beach, Calif.
To the Editor:
Re column, Feb. 10 :
Before Ross Douthat dismisses carbon taxes as falling heavily on the working class, he should study the just introduced in Congress, to almost no fanfare.
It will reduce emissions more than the Paris agreement or President Barack Obamas Clean Power Plan; it requires no big government spending; and it already has generated bipartisan support.
The critical difference between this legislation and other carbon tax proposals is that all fees collected would be returned directly to American households each month. Most of the working class will actually come out ahead if this legislation passes.
Its a Green New Deal right under our noses!
Laura SchumacherSan Diego
To the Editor:
Ross Douthats patronizing take on the ambitions of the Green New Deal misses the most critical point: Scientists agree that humanity has a very short window in which to transform our systems of generating and using energy.
The alternative is stronger, more frequent hurricanes, droughts, floods, famines and wildfires, costing lives and livelihoods on a global scale.
If this doesnt call for great ambition, what does?
Sarah RichardsonNew York
-------------------------------------------
What Is Chemical Bonding? | Chemistry Matters - Duration: 23:18.
>> host: Welcome back
to Chemistry Matters,
and the third video
on our Unit 4 playlist:
Chemical Bonding.
We've investigated some
of the characteristics of
intramolecular bonds,
specifically ionic
and covalent bonds,
which sit at either end
of the bond spectrum
we discussed in
the second video
for this unit.
Now let's go back out
to our classroom where
our students are learning
about types of bonds
that fall more in the middle
of the bonding spectrum.
>> professor: Remember earlier
how we said it's more accurate
to think of different types
of bonds as falling along
a spectrum, as opposed to
being one specific type?
Well, let's explore
a type of bond that falls
right in the middle
of that bond spectrum--
a polar covalent bond.
The reason polar covalent bonds
fall into the center
of the bond spectrum
in between ionic
and covalent
is because the atoms
that participate
in polar covalent bonding
have electronegativities
that are different
from each other.
But there just isn't
a large enough difference
for an electron to be
completely removed
from the atom with
the lower electronegativity.
The compound you're most
familiar with that has
polar covalent bonds is water.
In a water molecule,
we say the electrons that are
being shared between
the hydrogen atoms
and the oxygen atoms
are being shared unequally.
What we mean is that
the oxygen has
the greater electronegativity,
so it tends to keep
the electrons near itself.
Since the electrons
tend to stay near the oxygen
more than they do the hydrogen,
we say the oxygen end
of the molecule develops
a partially negative charge.
Meanwhile, think about
the hydrogen atom.
What did it start off with
in terms of electrons
and protons?
>> student: one proton
and one electron, right?
>> professor: Exactly,
but if its one electron
is spending most of its time
around the oxygen atom,
then what do you have left?
>> student: Just a proton?
So does that mean
the hydrogen ends of
the water molecules
are partially positive?
>> student: Yeah,
it's basically just
an exposed proton?
>> professor: That's exactly
right! And that's what makes
the water molecule polar.
It's similar to the way
a bar magnet has a north
and south pole.
Polar molecules have
a partially positive
and a partially negative end.
And these types of molecules
are characterized by chemists
as containing dipoles,
which simply means
that the molecule
has two poles,
similar to a bar magnet.
And in the same way
that two bar magnets
stick together
when brought close together
polar molecules
will also stick together,
with the partially negative end
of one molecule attracting to
the partially positive end
of the other molecule.
Now, let's compare
the polar covalent bond
to a nonpolar covalent bond,
like we explored earlier
with the hydrogen molecule.
Take a look at this image
of a chlorine molecule,
which is two chlorine atoms
bonded together.
Their electronegativities
are identical,
so there's no way there can be
a buildup of electrons
on either side
of the structure
like we saw with
the polar water molecule.
It's kind of like
a tug of war battle
in which the opponents
are evenly matched.
The rope stays taut
in the middle--
keeping both sides together.
That's how a nonpolar
covalent bond works.
The electrons spend equal time
with both atoms,
so equal attraction
to each atom.
>> host: By now,
you have a solid,
general understanding
of how intramolecular
bonding works.
You should also have
a better sense of
the various types,
or ranges of bonds
that hold matter together
to make up
our physical world.
So now we're going to learn
how to predict what kind of
intramolecular bond
a substance has,
and where that bond would lie
along the bond spectrum.
This activity will help you
visualize the types of bonds
that form as atoms
come together to make
molecules and compounds.
For this lab, our students
will use a simulation
of bonding that you can find
in our Chemistry Matters
Toolkit.
There you'll find instructions
on how to form bonds
between two or three atoms
and how to use atoms
with a wide range
of electronegativities
to form different kinds
of bonds.
The simulation will allow you
to conduct your own experiments
and collect data
about the types of bonds
you're forming.
So let's return to
our classroom
where our teacher and students
are getting some practice
with this bonding
simulation activity.
>> professor: Look at
the atoms, A and B.
Above them you can see
slider boxes that show
whether the atoms have high
or low electronegativity.
Notice that I have set
the slider bars
so that atom A and Atom B
both have the same
high electronegativity value.
Below the atoms
you can see a color-coded bar,
which is kind of like
the legend you find
on map.
This color bar is a key
for understanding the meaning
of colors in the electron
cloud drawing above.
Blue indicates an area
with strong positive charge.
Red indicates an area
with strong negative charge.
And the white bar color
indicates no strong charge.
Which is why the electron cloud
in this image is white.
Your job right now
is to look at some images
I've created by adjusting
the slider bars, like this one,
and use the data you see
to figure out what slider bar
combinations produce
ionic bonds,
which ones produce
polar covalent bonds,
which ones produce
mostly covalent bonds,
and which ones produce
non-polar covalent bonds.
So let's start with
this bond image.
I want to see if you can tell
what kind of bond it is.
Look at the two atoms,
A and B.
Does this image show
a partial positive
or negative charge
in this molecule?
>> student: It looks like
it doesn't have a charge.
The circles around
the atoms are white.
>> student: So what does
that mean?
>> professor: Remember,
the white electron cloud
around the molecule
indicates there's
no strong charge
on the molecule.
>> student: Yeah,
under the slider bars,
the molecule is identified
as being "more covalent."
That makes sense because
both atoms are pulling hard
on the shared electrons.
>> professor: You're correct.
The bar labeled bond character
tells us that it's a more
covalent bond.
A molecule like this,
remember, with no strong
partial positive
or negative charge,
is a nonpolar molecule.
So this is an example
of a nonpolar covalent bond.
>> host: Our students
have gotten a nice start
identifying and predicting
types of bonds.
Now they're going to continue
this activity by moving
the electronegativity
sliders themselves to create
different types of bonds.
This will help them
gather data and identify
patterns in the formation
of intramolecular bonds.
A lot of students
have found this to be
a very helpful exercise
for solidifying
their understanding
of bond types.
So before continuing
with the rest of this unit,
now is an excellent time
for you to get
some practice too.
In our Chemistry Matters
Toolkit, you'll find
the information needed
to perform this exercise.
You can use simulations
just like our students used,
and even manipulate
the properties of the bond types
by adjusting
the electronegativity sliders.
When you start the simulation,
make sure you click on
the Bond Character button
in the View box
and the Electrostatic Potential
in the Surface box.
This activity lets you
explore how the nature
of bonds that form
between atoms
is directly impacted
by the electronegativity
of the atoms.
You'll get to choose
how many new molecules
you form.
No matter how many
new molecules you choose
to form, make sure
you write down
the electronegativity
and the bond character
for each bond you create.
Then you'll be able to look
for patterns in your data.
Once you've practiced
identifying and predicting
types of bonds, rejoin me
for the next video
on the Unit 4 playlist
where we'll take a look
at the results our students
found with this activity.
I'll see you there!
-------------------------------------------
Trumping tax season: How the new tax code is hitting your wallet - Duration: 3:15.
For more infomation >> Trumping tax season: How the new tax code is hitting your wallet - Duration: 3:15. -------------------------------------------
Video of Luis Suarez's 'disasterclass' for Barcelona v Lyon is now doing the rounds - Duration: 3:45.
Luis Suarez's performances away from the Camp Nou in the Champions League are now a real concern for Barcelona fans
Many of them took to social media to criticise the Uruguayan striker on Tuesday night after his latest blank against Lyon - the 16th successive away game in Europe's premier cup competition in which he's failed to get on the scoresheet
Remarkably, Suarez has now gone 1,511 minutes away from home in the Champions League without scoring or even setting up a goal
His last goal on the road came back in September 2015 against AS Roma at the Stadio Olimpico
An increasing number of disgruntled Barça fans are losing patience with the 32-year-old, who joined the Catalan giants from Liverpool back in the summer of 2014
Some of them even want to see a new number nine come in to replace Suarez this summer
Spanish newspaper Marca rated Suarez as the worst Barcelona player on the pitch against Lyon, adding: "It wasn't his night as he was slow and off colour throughout
He worked tirelessly and tried hard, but without any success." That assessment, if anything, seems rather generous about Suarez's display - which has been described on social media as a 'disasterclass'
One fan has compiled Suarez's individual 'highlights' from the match into one two-minute video and it shows just how poor the South American was at the Parc Olympique Lyonnais
Watch it here. When he wasn't getting dispossessed, misplacing passes, miscontrolling the ball or spurning decent goalscoring opportunities, he wasn't doing much else
How he lasted the full 90 minutes, well, only Ernesto Valverde can answer that
Despite Suarez's woeful individual performance, though, Valverde backed his striker after the match
"It doesn't worry me," he insisted, per ESPN. "It would worry me if he wasn't getting chances, which is what you ask for from a centre-forward
"And [even] if he doesn't have chances, he creates them for his teammates. Opponents are frightened of him
He [must] be reserving himself. Football is a game of margins. Strikers have runs [of goals] and the best thing is he's getting chances
" But unless he rediscovers his scoring boots, it's hard to see Barça winning the Champions League this season
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