From 15 mol of Silver nitrate, the moles of silver chloride produced have been 15 mol. Thus, option B is correct.
The balanced chemical reaction for the synthesis of silver chloride has been:

From the balanced equation, since there has presence equal moles of silver nitrate and sodium chloride, the moles of silver chloride formed has been equivalent. Thus, 1 mole of silver nitrate gives 1 mole of silver chloride.
The moles of silver nitrate available are, 
The moles of silver nitrate produced can be given as:

Thus, the moles of silver chloride produced have been 15 mol. Thus, option B is correct.
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brainly.com/question/10606802
On absorbing energy, an electron moves to an excited state (unstable state) from its ground state (stable state). Since the electron is in unstable state so it tends to rearrange itself to return to its lowest energy state. On returning to lowest energy state which is stable, it releases energy in the form of light.
Hence, option A that is the electron releases energy in the form of light on falling to lower energy state from excite state.
Answer:
Nonmetal + Nonmetal —> covalent compound (usually)
Explanation:
Covalent compounds are formed when two nonmetals react with each other.
Watt stands for power that is energy per unit time