The oxidation number of hydrogen in HNC is +1.
In fact, the oxidation number of hydrogen in any compound will generally be +1; a major exception would be in the case of metal hydrides (e.g., NaH), where the hydrogen exists as a negative ion.
So to put them all in the same units we have
<span>2500 mL </span>
<span>250 mL </span>
<span>25mL </span>
<span>2,500,000,000mL </span>
<span>So the third one is the smallest</span>
Yes. If this is the balanced equation:
AlCl3 + 3Na —— 3NaCl + Al
then Al was reduced from a 3+ oxidation (to neutralize the 3- from the chlorine) to a 0 oxidation (elemental ground state).
Standard equation would be N2(g)+3H2(g)==>2NH3(g), so through stoichiometry, (4 mol N2)(2mol NH3/1 mol N2), assuming excess H2, would yield 8 moles of NH3.