Combined Foundation

Question 1

What is the Law of conservation of Mass?

Answer 1

In chemical reactions, atoms are not created or destroyed, just rearranged.
The mass before = the mass after

Question 2

When might the mass of a reaction increase?

Answer 2

When a reactant is a gas (i.e oxygen has been added)

Question 3

When might the mass of a reaction decrease?

Answer 3

When a product is a gas and escapes

Question 4

What is relative formula mass (Mr or RMM)?

Answer 4

The sum of the relative atomic masses (Ar) of each atom in a substance.

Question 5

What re the four state symbols and what do they stand for?

Answer 5

(s) - solid, (l) - liquid, (g) - gas, (aq) - aqueous or dissolved in water.

Question 6

How can you tell when a symbol equation is balanced?

Answer 6

the number of atoms of each element is the same on both sides

Question 7

What is a unit for concentration?

Answer 7

g/dm³

Question 8

Which formula is used to calculate concentration from mass and volume?

Answer 8

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

Question 9

Which formula is used to calculate mass from concentration and volume?

Answer 9

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

Question 10

How can you convert a volume reading in cm³ to dm ³?

Answer 10

divide by 1000

Question 11

If the amount of solute in a solution is increased , what happens to it’s concentration?

Answer 11

increases

Question 12

If the amount of water in a solution is increased, what happens to concentration?

Answer 12

decreases

Question 13

What is a solute?

Answer 13

The solid that dissolves

Question 14

What is a solvent?

Answer 14

The liquid that does the dissolving

Question 15

What is a solution?

Answer 15

The mixture that is created when a solute dissolves in a solvent.