Eight because an octet has 8 electrons and when it’s full it’s stable. If it’s not full, it’s constantly sharing or borrowing electrons.
The concentration of the Nitric acid solution : 0.114 M
<h3>Further explanation </h3>
Titration is a procedure for determining the concentration of a solution (analyte) by reacting with another solution whose known concentration (usually a standard solution) is called the titrant. Determination of the endpoint/equivalence point of the reaction can use indicators according to the appropriate pH range
Titrations can be acid-base titration, depositional titration, and redox titration. An acid-base titration is the principle of neutralization of acids and bases
Reaction
HNO₃ + NaOH → NaNO₃ + H₂O
Concentration a standard solution of sodium hydroxide : 0.0998 mol/dm³ , and the volume = 25 cm³
moles NaOH=

<em>From the equation, mol ratio HNO₃ : NaOH = 1 : 1, so mol HNO₃ = mol NaOH=</em><em>2.495 mlmoles</em>
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The volume of HNO₃ = 21.8 cm³, so the concentration :

Answer: 6 moles
Take a look at the balanced chemical equation for this synthesis reaction
N 2(g] + 3 H 2(g] → 2 NH 3(g]
Notice that you have a 1:3 mole ratio between nitrogen gas and hydrogen gas. This means that, regardless of how many moles of nitrogen gas you have, the reaction will always consume twice as many moles of hydrogen gas.
So, if you have 2 moles of nitrogen taking part in the reaction, you will need
2 moles N 2 ⋅ 3 moles H 2 /1 mole N 2 = 6 moles H 2