C3- Quantitative chemistry

Question 1

relative formula mass

Answer 1

sum of all the relative atomic masses of atoms in a formula

example: Cl= 35.5

Question 2

Calculating Percentage Mass of an Element in a Compound

Answer 2

relative atomic mass x number of atoms of that element/
relative atomic mass of the compound

Question 3

conservation of mass (example)

Answer 3

2Mg + O2 →2MgO
(2 × 24) + (2 × 16) →2(24 + 16)
48 + 32→ 2 × 40
80 →80

Question 4

concentration

Answer 4

amount of a substance in a specific volume of a solution.

Question 5

calculation of the concentration of a solution

Answer 5

concentration (g/dm3) = mass (g)÷ volume of solvent (dm3)

Question 6

rearranged calculation of the mass of the dissolved substance

Answer 6

mass (g) = concentration (g/dm3) × volume (dm3)