C3 quantitive chemistry

Question 1

what is the law of conservation of mass

Answer 1

no atoms are created or destroyed during a chemical reaction (mass of products = mass of reactants)

Question 2

what is relative formula mass

Answer 2

the combined atomic mass in an equation

Question 3

does mass change when the product or reactant is a gas

Answer 3

yes

Question 4

what is the equation linking mr, mass and moles

Answer 4

mass= mr*moles

Question 5

what is Avogadro’s constant

Answer 5

the number of atoms in any given mole is 6.02*10^23

Question 6

how do you use moles to balance equations

Answer 6

a. convert the masses in grams to amounts in moles
b. convert the numbers of moles to simple whole number ratios then you know how many moles you have of one element/compound compared to another

Question 7

what is a limiting reactant

Answer 7

the reactant that is used up

Question 8

how do you work out the percentage yield

Answer 8

amount of product produces/maximum amount of product possible * 100

Question 9

what is the equation for moles

Answer 9

moles = volume * concentration

Question 10

volume of gas at room temperature equals what?

Answer 10

moles * 24