Answer:
0.96 mole of CH4.
Step-by-step explanation:
From a background knowledge of gas laws, we understood that 1 mole of a gas occupy 22.4 L at STP. This implies that 1 mole of CH4 also occupy 22.4 L at STP.
Now, we shall determine the number of mole of CH4 that will occupy 21.5 L at STP. This is illustrated below:
1 mole of CH4 occupied 22.4 L at STP.
Therefore, Xmol of CH4 will occupy 21.5 L at STP. i.e
Xmol of CH4 = (1 × 21.5)/22.4
Xmol of CH4 = 0.96 mole
Therefore, 0.96 mole of CH4 will occupy 21.5 L at STP.