Your mass can never change no matter where you are since mass is the amount of matter you contain. By going to the moon, you do become lighter due to the weaker gravity but the amount of matter that you are made of (your mass) does not change.
I hope the helps. Let me know if anything is unclear.
Answer:
After increasing the volume, we have 1.81 moles of hydrogen gas in the container
Explanation:
Step 1: Data given
Number of moles hydrogen gas (H2) = 1.24 moles
Volume of hydrogen gas (H2° = 27.8 L
The final volume is increas to 40.6 L
Step 2: Calculate the new number of moles
V1/n1 = V2/n2
⇒with V1 = the initial volume = 27.8 L
⇒with n1 = the initial number of moles H2 = 1.24 moles
⇒with V2 = the final volume = 40.6 L
⇒with n2 = the new number of moles = TO BE DETERMINED
27.8L / 1.24 moles = 40.6 L / n2
n2 = 40.6 / (27.8/1.24)
n2= 1.81 moles
After increasing the volume, we have 1.81 moles of hydrogen gas in the container