Explanation:
Expression for the
speed is as follows.

where,
= root mean square speed
k = Boltzmann constant
T = temperature
M = molecular mass
As the molecular weight of oxygen is 0.031 kg/mol and R = 8.314 J/mol K. Hence, we will calculate the value of
as follows.

= 
= 498.5 m/s
Hence,
for oxygen atom is 498.5 m/s.
For nitrogen atom, the molecular weight is 0.028 kg/mol. Hence, we will calculate its
speed as follows.

= 
= 524.5 m/s
Therefore,
speed for nitrogen is 524.5 m/s.
Answer:
moles = given mass/atomic mass
so H2O mass = 2 +16=18
so 12g of h2o= 12/16 = 3/4 moles
Answer:
First one: group
Second one: period
Third one: number of valence electrons
Last one: increases
I believe that would be Cadmium Permaganate
Hope that helped :)