<span>According to octet rule, atoms with an atomic number less than 20 tend to combine with other atom such that both of these atoms have eight electrons in their valence shells, which gives them the same electronic configuration as that of noble gas.
However, there are few compound that donot obey octel rule. Among the elements mentioned above i.e. oxygen and helium obeys octet rule.
In case of nitrogen, oxide of nitrogen (like NO and NO2) have incomplete octet.
While there are few compounds of Br wherein Br has expanded octet. For example, in BrF5, Br has 12 electrons in valence shell. </span>
Answer: A
Explanation: Beta particles have a charge of -1
Yes that’s correct it is B
Because the intention is to boil the solution, the purpose of the solvent is to dissolve so it has a higher boiling point so ensure it stays in liquid form and doesn't evaporate into a gas
also, a pure solvent is made of 1 substance so it has 1 boiling point and the solution must evaporate/boil first