EL9

Question 1

How to work out the mass of products when given mass of reactant?

Answer 1

1. Write a balanced equation 2. Work out moles of reactants and products 3. Calculate the molecular mass of reactants and products 4. Work out the masses of the products from the mass that was reacted

Question 2

What is the definition of an acid?

Answer 2

A substance that donates H⁺ un a chemical reaction

Question 3

What is the definition of a base?

Answer 3

A substance that accepts H⁺ in a chemical reaction.

Question 4

What does a H⁺ correspond to? Why?

Answer 4

A proton.
H⁺ ion consists of only a proton and an electron.

Question 5

What is the Bronsted-Lowry theory?

Answer 5

That acids donate H⁺ ions and bases accept them.

Question 6

What is present in every solution of an acid in water?

Answer 6

The oxonium ion - H₃0⁺

Question 7

What is an alkali?

Answer 7

A base that dissolves in waterto produce hydroxide ions, OH^-

Question 8

What is the ionic equation for a neutralization reaction?

Answer 8

H⁺_(aq) + OH^- → H₂O_(l)

Question 9

What do you need to do to find out the exact volume at neutralisation occurs?

Answer 9

• Dilute a solution
• Make up a standard solution
• Carry out an acid-base titration

Question 10

How do you convert g cm^-3 to mol dm^-3?

Answer 10

concentration (dm^-3) = concentration (g dm-3) / molar mass (g mol-1)