Answer : The volume of 
is 14.784 L.
Solution : Given,
Mass of Aluminium = 6 g
Molar mass of Aluminium = 27 g/mole
First we have to calculate the moles of aluminium.
Moles of Al = 
The given balanced reaction is,
From the reaction, we conclude that
2 moles of Al react with the 6 moles of
0.22 moles of Al react with 
of
At STP, 1 mole contains 22.4 L volume
As, 1 mole of contains 22.4 L volume of
0.66 moles of contains 
volume of
Therefore, the volume of is 14.784 L.
Answer: b for the first a for the second sorry if its wrong
Explanation:
Should be an igneous rock.
First, we need to assume acetylene to adapt an ideal gas behavior. So, we can use the Ideal Gas Law:
PV = nRT
Given:
V = 42 L
T = 305 K
P = 780 torr = 1.026 atm
R = gas constant, 0.0821 L atm/ mol K
n = amount of gas in the canister
1.026 atm * 42 L = n * 0.0821 L atm/mol K * 305 K
n = 1.72 moles of gas
