masses in reactions

Question 1

what does the law of conservation of mass state?

Answer 1

no atoms are lost or made during
reactions so the mass of the products equals the mass of the reactants.

Question 2

what is the relative formula mass of a compound?

Answer 2

sum of the relative atomic masses of
all the atoms shown in the formula.

Question 3

In a balanced equation, what does the sum of the relative formula masses of all the reactants equal?

Answer 3

the sum of the relative formula masses of all the products.

Question 4

what is the mole of a substance?

Answer 4

its relative atomic mass or relative formula mass in grams.

Question 5

what is the Avogadro constant?

Answer 5

The number of atoms, molecules or ions in a mole of a substance is always 6.02 x 10 to the power of 23

Question 6

equation for moles

Answer 6

mass (g) / Ar or mass (g)/ Mr

Question 7

what does a balanced equation show?

Answer 7

the number of moles of each substance
involved in the reaction.

Question 8

what is a limiting reactant?

Answer 8

The reactant that gets used up first in a reaction. This is the
reactant that is NOT in excess.