Official 52 Set 5 Snowflakes And Ozone
What aspects of snowflakes does the professor mainly discuss?
A. How they develop into complex structures
B. How they are affected by the presence of ozone方向反了
C. The challenges researchers face in studying them并没有注意说challenge
D. The function of their quasi-liquid layer
What factor helps explain why no two snowflakes are alike?
A. They all freeze at different rates.
B. They all form in slightly different air temperatures.
C. They all begin with a different number of water molecules.
D. They all follow different paths through clouds.
这个就是一句话
Listen to part of a lecture in a chemistry class.
Ok today we are going to talk about the Arctic, ozone depletion, and snowflakes.
Now, I find snowflakes fascinating.
Even though there's been a lot of research.
That radiate out from it.
Well, you start with water vapor. You need a pretty humid atmosphere. And that water vapid condenses into ice, into an ice crystal.
Like a thin dinner plate that rather than being circular, is hexagonal, with six flat edges.
Imagine this snowflake is floating around in the wind.
Molecules from that vapid attach to each of the six sides.
You begin to see the development of six arms or branches radiate out from the center plate.
More molecules attach to it, leading to more and more complex structures.
Each snowflake takes a unique route through the clouds on its way down.
And so, the quantity of water vapor that it goes through is going to be unique for each one.
A quasi-liquid layer.
Our snowflake is an ice flake, right?
Though the thickness varies at different temperatures.
The molecules bond together and they get sort of locked in the place.
The exterior of the ice.
Think of a brick wall.
They have other bricks above and below them.
Bricks don’t move at all. They are not liquid.
But the bricks were water molecules.
The quasi-liquid layer.
Ozone is a gas found in the atmosphere of Earth.
In the stratosphere.
Which helps block harmful radiation from the Sun.
It can be a pollutant.
Quasi-liquid layer.
