<u>Answer:</u> The mass of nitrogen gas reacted to produce given amount of energy is 5.99 grams.
<u>Explanation:</u>
The given chemical reaction follows:

We know that:
Molar mass of nitrogen gas = 28 g/mol
We are given:
Enthalpy change of the reaction = 14.2 kJ
To calculate the mass of nitrogen gas reacted, we use unitary method:
When enthalpy change of the reaction is 66.4 kJ, the mass of nitrogen gas reacted is 28 grams.
So, when enthalpy change of the reaction is 14.2 kJ, the mass of nitrogen gas reacted will be = 
Hence, the mass of nitrogen gas reacted to produce given amount of energy is 5.99 grams.
For balancing acidic solutions, we would need to add H+ ions to the correct side of the equation to balance the total number of atoms and the overall charge.
For a reaction to occur, there should be mobility of ions in reactant side.
If the reactant is larger, its mobility will be lesser than that of smaller ones.
So reactants smaller in size have higher mobility which makes reaction faster.
Hence D is the correct option.
Hope this helps, have a great day/night ahead!
Answer:
D) N2O5
Explanation:
The molar mass of a substance is defined as the mass of this substance in 1 mol. To solve this question we must find the molar mass of each option:
<em>Molar mass NO:</em>
1N = 14g/mol*1
1O = 16g/mol*1
14+16 = 30g/mol
<em>Molar mass NO2:</em>
1N = 14g/mol*1
2O = 16g/mol*2
14+32 = 46g/mol
<em>Molar mass N2O:</em>
2N = 14g/mol*2
1O = 16g/mol*1
28+16 = 44g/mol
<em>Molar mass N2O5:</em>
2N = 14g/mol*2
5O = 16g/mol*5
28+80 = 108g/mol
That means the compound with the greatest mass is:
<h3>D) N2O5</h3>