1. What does the Law of conservation of mass state? a. According to the Law of Conservation, what is true about the masses of the reactants and the products in a chemical reaction?
b. Find the missing mass in the reactions below:

MgO + H2O → Mg(OH)2
12.4 g ? 21.8

According to the law of conservation of mass, the mass of the products in a chemical reaction must equal the mass of the reactants. The law of conservation of mass is useful for a number of calculations and can be used to solve for unknown masses, such the amount of gas consumed or produced during a reaction.

i wish i could but this one is weird give me abc and i can solve it.

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.