Its a single Displacement reaction
It would be 4.2, hope this helps.
<span>
Low pH means the solution is acidic; if the solution is acidic, that
means that there are hydronium ions in solution (H3O+). For example,
hydrochloric acid dissolves into H+ ions and Cl- ions, and the H+ ions
rreact with water like this:
H+ + H2O --> H3O+
If you want to get mathematical, pH is defined as the negative log of the concentration of hydronium ions.
Thus, if there are a lot of hydronium ions, the solution will have a low, or acidic, pH. Hope this helps^-^</span>
Answer:
6.67 moles
Explanation:
Given that:-
Moles of hydrogen gas produced = 10.0 moles
According the reaction shown below:-

3 moles of hydrogen gas are produced when 2 moles of aluminium undergoes reaction.
Also,
1 mole of hydrogen gas are produced when
moles of aluminium undergoes reaction.
So,
10.0 moles of hydrogen gas are produced when
moles of aluminium undergoes reaction.
<u>Moles of Al needed =
moles = 6.67 moles</u>