Asample of gas contains 0.1300 mol of n2(g) and 0.2600 mol of o2(g) and occupies a volume of 23.9 l. the following reaction takes place: n2(g) + 2o2(g)2no2(g) calculate the volume of the sample after the reaction takes place, assuming that the temperature and the pressure remain constant.

Answer : The volume of the sample after the reaction takes place is, 15.93 liters.

Explanation : Given,

Moles of = 0.13 mole

Moles of = 0.26 mole

Initial volume of gas = 23.9 L

First we have to calculate the moles of gas.

The balanced chemical reaction is :

From the balanced reaction, we conclude that

As, 1 mole of react with 2 moles of to give 2 moles of .

So, 0.13 mole of react with moles of to give moles of .

According to the Avogadro's Law, the volume of the gas is directly proportional to the number of moles of the gas at constant pressure and temperature.

or,

where,

= initial volume of gas = 23.9 L

= final volume of gas = ?

= initial moles of gas = 0.13 + 0.26 = 0.39 mole

= final moles of gas = 0.26 mole

Now put all the given values in the above formula, we get the final temperature of the gas.

Therefore, the volume of the sample after the reaction takes place is, 15.93 liters.

the answer is b because, investigating whether another species of moth also drinks tears might be interesting, but it would not directly explain why this species of moth does.

to explain why this species of moth drinks tears, the scientist could ask: "what nutrients that moths need are in elephant tears? "

the scientist could experiment with moth repellent or oter ways to keep the moths away, but that would not answer his original question.