Which numbers are shown in the symbol for a radioactive nuclide?

atomic and mass number

Explanation:

Radioactive decay process is a type of process in which a less stable nuclei decomposes to a stable nuclei by releasing some radiations or particles like alpha, beta particles or gamma-radiations. The radioactive decay follows first order kinetics.

General representation of a radioactive nuclide is given as:  

where,

Z represents Atomic number

A represents Mass number

X represents the symbol of an element

Thus atomic and mass numbers are shown in the symbol for a radioactive nuclide.

the equation that correctly represent the reaction for formation of ammonia is

n2+ 3h2 → 2nh3 (answer d)

1 mole of nitrogen gas (n2) react with 3 moles of hydrogen gas (h2) to form 2 moles of ammonia ( nh3). this is in a process known as haber process were iron is used as a catalyst and reaction take place that a higher temperature and pressure. the process is exothermic hence energy is released.