The heat of vaporization for water is 40.7 kJ/mol. A given amount of water requires 63.8 kJ of energy to boil. The mass of the sample of water is -

Alpha particles have positive charge, beta particles have negative charge, and answer 4 just doesn’t make sense. thus, you are left with only one possible answer.

Heat is involved in chemical change in two ways; chemical changes either result in heat being added to or removed from an object, and chemical changes require a certain amount of heat before they can take place.

The total number of nucleons