2Al + 6HCl → 2AlCl3 + 3H2 If 12 moles of Al completely react, how many moles of H2 are produced?

18 moles of H₂.

Explanation:

The balanced equation for the reaction is given below:

2Al + 6HCl –> 2AlCl₃ + 3H₂

From the balanced equation above,

2 moles of Al reacted to produce 3 moles of H₂.

Finally, we shall determine the number of mole of H₂ produced by the reaction of 12 moles of Al. This can be obtained as follow:

From the balanced equation above,

2 moles of Al reacted to produce 3 moles of H₂.

Therefore, 12 moles of Al will react to produce = (12 × 3)/2 = 18 moles of H₂.

Thus, 18 moles of H₂ were obtained from the reaction.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.