Answer:
you sure it is the right sign your using
The correct matches are:
1. Exosphere - Temperatures reach as high as 2000 C yet it feels very cold
This is the top layer of the atmosphere. The atoms are so dispersed that despite it having very high temperature it doesn't feel like it at all.
2. Thermosphere - Particles that have enough energy can escape into space
The thermosphere is the fourth highest layer of the atmosphere. The atoms in this layer are relatively distant from one another, so the particles that have enough energy manage to escape easily into the exosphere and then the space.
3. Mesosphere - It is the coldest region of the atmosphere
The mesosphere is the third highest layer. In this layer the temperatures constantly drop, and they go down to -85 degrees, making it the coldest layer by far.
4. Stratosphere - Ninety percent ozone is in this layer
The startosphere has a separte zone in it which is dominated by only one gas, the ozone. It is called the ozone layer, the one that protects the Earth from too intense UV radiation, and in fact over 90% of this gas is locate here.
5. Troposphere - It is warm due to the heat from Earth's surface
The troposphere is the densest and lowest of the layers. It is the one that also has Greenhouse gases which manage to trap the heat that is radiated from the surface of the Earth, thus keeping this layer relatively warm.
Answer: 12 L fluorine gas at STP can be collected from the decomposition of 90.7 g of 
Explanation:
The balanced decomposition reaction is shown as
moles of 
According to stoichiometry:
2 moles of gives = 3 moles of flourine gas
Thus 0.36 moles of gives = 
of flourine gas
Using ideal gas equation :
P = pressure of gas = 1 atm ( at STP)
V = Volume of gas = ?
n = moles of gas = 0.54
R = gas constant = 0.0821 L atm/Kmol
T = temperature = 273 K ( at STP)
Putting the values we get :
Thus 12 L fluorine gas at STP can be collected from the decomposition of 90.7 g of
