In a balanced chemical reaction, the total mass of the products always equals the a. molar mass of the reactants. c. total mass of the reactants. b. atomic mass of the reactants. d. proportional masses of the reactants.

c. total mass of the reactants.

Explanation:

According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

For Example:

Mass of hydrogen =

Mass of oxygen =

Mass of water =

Mass of products = mass of water = 36 grams

Thus mass or reactant = mass  of hydrogen + mass of oxygen = 4 g + 32 g = 36 g

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.