Question

which statement is true about this reaction?

14/7n + 1/1h → 15/8o

its product is heavier than each of its reactants.

it occurs only outside the solar system.

it is a practical source of energy on earth.

it shows the critical mass of an element.

Explanation:

• Mass comparison:
• The mass number of \(^{14}_{7}\text{N}\) is \(14\), the mass number of \(^{1}_{1}\text{H}\) is \(1\), and the mass number of \(^{15}_{8}\text{O}\) is \(15\).
• The mass of the product \(^{15}_{8}\text{O}\) (\(m = 15\) atomic mass units) is equal to the sum of the masses of the reactants (\(14 + 1=15\) atomic mass units). But in reality, in nuclear reactions, we consider the actual atomic masses (taking into account binding energy). The atomic mass of \(^{14}_{7}\text{N}\approx14.003\) u, \(^{1}_{1}\text{H}\approx1.0078\) u, and \(^{15}_{8}\text{O}\approx15.003\) u. The product \(^{15}_{8}\text{O}\) is heavier than each of the reactants when considered individually.
• Occurrence:
• Nuclear reactions like this can occur in stars (which are part of the solar system). For example, similar fusion - like reactions (involving light nuclei) occur in the Sun (a star in our solar system). So the statement “It occurs only outside the solar system” is false.
• Practical energy source:
• Nuclear fusion reactions on Earth are still in the experimental stage (e.g., in tokamaks). Fission (not this particular reaction) is used in nuclear power plants. This reaction (\(^{14}_{7}\text{N}+^{1}_{1}\text{H}\to^{15}_{8}\text{O}\)) is not a practical source of energy on Earth currently.
• Critical mass:
• Critical mass is a concept related to nuclear fission (e.g., for \(^{235}\text{U}\) fission). This is a nuclear reaction (not fission) and has no relation to critical mass.

Answer:

Its product is heavier than each of its reactants.