Answer:
hot air rises because gases expand as they heat up.When air heats up and expands,its density also increases.The warmer,less dense air effectively floats on top of the colder, dense air below it. This creates a buoyant force that causes warmer air to rise.
cold air sinks because it is heavier as its more dense ( because of closely packed molecules) soits harder for them to move and they absorb less energy. Also, gravity pulls on it more strongly.
Hope it helps :)
Answer:1. ![Rate=k[CHCl_3]^1[Cl_2]^\frac{1}{2}](https://tex.z-dn.net/?f=Rate%3Dk%5BCHCl_3%5D%5E1%5BCl_2%5D%5E%5Cfrac%7B1%7D%7B2%7D)
2. The rate constant (k) for the reaction is 
Explanation:
Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.
![rate=k[CHCl_3]^x[Cl_2]^y](https://tex.z-dn.net/?f=rate%3Dk%5BCHCl_3%5D%5Ex%5BCl_2%5D%5Ey)
k= rate constant
x = order with respect to 
y = order with respect to 
n = x+y= Total order
1. a) From trial 1: ![0.0035=k[0.010]^x[0.010]^y](https://tex.z-dn.net/?f=0.0035%3Dk%5B0.010%5D%5Ex%5B0.010%5D%5Ey)
(1)
From trial 2: ![0.0069=k[0.020]^x[0.010]^y](https://tex.z-dn.net/?f=0.0069%3Dk%5B0.020%5D%5Ex%5B0.010%5D%5Ey)
(2)
Dividing 2 by 1 :![\frac{0.0069}{0.035}=\frac{k[0.020]^x[0.010]^y}{k[0.010]^x[0.010]^y}](https://tex.z-dn.net/?f=%5Cfrac%7B0.0069%7D%7B0.035%7D%3D%5Cfrac%7Bk%5B0.020%5D%5Ex%5B0.010%5D%5Ey%7D%7Bk%5B0.010%5D%5Ex%5B0.010%5D%5Ey%7D)
therefore x=1.
b) From trial 2: (3)
From trial 3: ![0.0098=k[0.020]^x[0.020]^y](https://tex.z-dn.net/?f=0.0098%3Dk%5B0.020%5D%5Ex%5B0.020%5D%5Ey)
(4)
Dividing 4 by 3:![\frac{0.0098}{0.0069}=\frac{k[0.020]^x[0.020]^y}{k[0.020]^x[0.010]^y}](https://tex.z-dn.net/?f=%5Cfrac%7B0.0098%7D%7B0.0069%7D%3D%5Cfrac%7Bk%5B0.020%5D%5Ex%5B0.020%5D%5Ey%7D%7Bk%5B0.020%5D%5Ex%5B0.010%5D%5Ey%7D)
therefore 
![rate=k[CHCl_3]^1[Cl_2]^\frac{1}{2}](https://tex.z-dn.net/?f=rate%3Dk%5BCHCl_3%5D%5E1%5BCl_2%5D%5E%5Cfrac%7B1%7D%7B2%7D)
2. to find rate constant using trial 1:
![0.0035=k[0.010]^1[0.010]^\frac{1}{2}](https://tex.z-dn.net/?f=0.0035%3Dk%5B0.010%5D%5E1%5B0.010%5D%5E%5Cfrac%7B1%7D%7B2%7D)
Explanation:
Gases are very less denser also, they've negligible intermolecular force of attraction between the particles of the gas. So, they all are free to roam seperately and hence making a negligible volume for which they become heavy settle down.
