Answer:
A) 
Explanation:
m = Mass of water = 38.9
M = Molar mass of water = 18 g/mol
= Avogadro's number = 
The reaction of electrolysis would be

Number of moles of 

From the reaction it can be seen that 2 moles of
gives 1 mole of 
So, number of moles of
produced is

Number of molecules

So,
of oxygen is produced.
Answer
D
Explanation:
They take up usable forms of nitrogen found in soil
The Answer should be A Light particle
Moles of Zn: 26 / 65 = 0.4
Moles of S: 12.8 / 32 = 0.4
Molar ratio of Zn : S = 1 : 1
Empircal formula: ZnS
The answer is C
Units to measure pressure are as follows
atm - atmospheric pressure units
kPa - kilo Pascals
mm Hg - milimeters Hg
conversion units are;
1 atm = 101 325 Pa
therefore 4.30 atm = 101 325 Pa / atm x 4.30 atm = 435.7 Pa
1 atm = 760.0 mm Hg
4.30 atm = 760.0 mm Hg / atm x 4.30 atm = 3268 mm Hg
answers are 435.7 Pa and 3268 mm Hg