The answer would be C. Hope this helps
Answer:- C. 16.4 L
Solution:- The given balanced equation is:

From this equation, there is 2:1 mol ratio between HCl and hydrogen gas. First of all we calculate the moles of hydrogen gas from given grams of HCl using stoichiometry and then the volume of hydrogen gas could be calculated using ideal gas law equation, PV = nRT.
Molar mass of HCl = 1.008 + 35.45 = 36.458 gram per mol
The calculations are shown below:

= 
Now we will use ideal gas equation to calculate the volume.
n = 0.672 mol
T = 25 + 273 = 298 K
P = 101.3 kPa = 1 atm
R = 
PV = nRT
1(V) = (0.672)(0.0821)(298)
V = 16.4 L
From calculations, 16.4 L of hydrogen gas are formed and so the correct choice is C.
Answer:
option A = C₂H₄ + 3O₂ → 2CO₂ + 2H₂O
Explanation:
Law of conservation of mass:
This law stated that mass can not be created or destroyed in chemical reaction. It just changed from one to another form.
For example:
C₂H₄ + 3O₂ → 2CO₂ + 2H₂O
28 g + 96 g = 88 g + 36 g
124 g = 124 g
This reaction correctly hold the law of conservation of mass.
Other options:
C + 4H₂ → CH₄
12 g + 8g = 16 g
20 g = 16 g
This reaction do not hold the law of conservation of mass.
3H₂O → 3H₂ + 3O₂
54 g = 6 g + 96 g
54 g = 102 g
This reaction do not hold the law of conservation of mass.
2Na + Cl → NaCl
46 g + 35.5 g = 58.5 g
81.5 g = 58.5 g
This reaction do not hold the law of conservation of mass.