Acids and Bases

Question 1

What is an acid ?

Answer 1

a proton donor

Question 2

What is the formula for sulfuric acid ?

Answer 2

H2SO4

Question 3

What is the formula for hydrochloric acid ?

Answer 3

HCl

Question 4

What is the formula for nitric acid ?

Answer 4

HNO3

Question 5

What is the formula for ethanoic acid ?

Answer 5

CH3COOH

Question 6

What happens when an acid is added to water ?

Answer 6

it dissociates, releasing H+ ions

Question 7

What happens when a strong acid is added to water ?

Answer 7

it fully dissociates

Question 8

What happens when a weak acid is added to water ?

Answer 8

it partially dissociates

Question 9

What is a base ?

Answer 9

a proton acceptor

Question 10

What is the formula for sodium hydroxide ?

Answer 10

NaOH

Question 11

What is the formula for potassium hydroxide ?

Answer 11

KOH

Question 12

What is the formula for ammonia ?

Answer 12

NH3

Question 13

What is an alkali ?

Answer 13

a base that dissolves in water

Question 14

What is neutralisation ?

Answer 14

when an acid reacts with a base

Question 15

What is the equation for neutralisation ?

Answer 15

acid + base -> salt + water

Question 16

What is the ionic equation for an acid and alkali reaction ?

Answer 16

H+ (aq) + OH- (aq) => H2O (l)

Question 17

What are the observations for neutralisation of solutions ?

Answer 17

no observable reaction

Question 18

What are the observations for neutralisation of a metal oxide or hydroxide ?

Answer 18

solid dissolving

Question 19

What is meant by concordant ?

Answer 19

results that are within 0.1 cm^3 of each other

Question 20

What are the products of reacting an acid and a metal oxide ?

Answer 20

salt + water

Question 21

What are the products of reacting an acid and a metal hydroxide ?

Answer 21

salt + water

Question 22

What are the products of reacting an acid and a metal carbonate ?

Answer 22

salt + water + carbon dioxide

Question 23

What would you observe when reacting an acid with a metal carbonate ?

Answer 23

• fizzing
• solid dissolving

Question 24

How do you make a standard solution ?

Answer 24

1. measure a known mass of solid and dissolve in approx. 100 cm^3 of water in a beaker
2. transfer to a 250 cm^3 volumetric flask, rinse the beaker and add washings to the flask
3. make up to the mark with distilled water, using the bottom of the meniscus at eye level
4. invert flask several times to mix thoroughly

Question 25

How do you perform a titration ?

Answer 25

1. using a pipette, measure a known volume of a solution into a conical flask 2. pour the other solution into a burette and record the initial volume 3. add a few drops of indicator to the solution in the conical flask 4. add the solution in the burette to the solution in the conical flask, until the reaction is just completed. This is the end point (colour change seen). Record the final volume. 5. Calculate the solution added from the burette (the titre). 6. Repeat the experiment, adding the solution in the burette drowse, until there are two concordant titres. 7. Calculate a mean titre, using only the closest titres.