What volume of hydrogen (in L) is produced from the complete reaction of 56.49 g of magnesium metal at stp? (Mg= 24.30 g/mol)

Mg(s) + 2HCl(aq) -> MgCl2(aq) + H2(g)

Hint: 1 mole of gas at stp occupies 22.4 L

Alidded glass container is filled with a colored gas. after a period of time, it is observed that the gas is uniformly spread throughout the box and that the movement has slowed considerably. next, a warm iron plate is carefully placed under the box. why is there resumed movement of the gas in the container?

Sum of brother and sisters age is 26. four times the brothers age is subtracted from three times the sisters age, the difference is 8. what are the ages of the brother and sister?

Ab c or d ? i’m not sure what the answer is