Acid and alkaline

Question 1

Acid components

Answer 1

Sour
Conducts electricity
Reacts with alkali and metal

Question 2

Acid in lab HSN

Answer 2

[S] Hydrochloric acid (toilet cleaners)
[S] Sulphuric acid (fertilisers, dyes and paints)
[S] Nitric acid

Question 3

Acid usage

Answer 3

As preservatives
Removing stains
Making industrial chemicals

Question 4

Alkalies components

Answer 4

Bitter and slippery
Conduct electricity
React with acid

Question 5

Alkali in lab SAC

Answer 5

[S] Sodium hydroxide (drain cleaners)
[N] Ammonia solution (kitchen cleaners, glass cleaners)
Calcium hydroxide (limewater)

Question 6

Alkali usgae

Answer 6

Removing grease
Making industrial chemicals ([S] potassium H –> batteries)

Question 7

Indicators

Answer 7

Show presence of acids and alkalis

Question 8

Precautions when handling chemical substances

Answer 8

1. Hazard warning labels on reagent bottles
2. Wear safety goggles and put on protective gloves
3. Pour waste in appropriate bottles
4. Wash hand thoroughly after experiment

Question 9

Remedial measures

Answer 9

1. Wash affected area under slow running water
2. Remove contaminated clothing without making contact
3. Wash with eye bottle
4. Call ambulance

Question 10

Four methods for acid/alkali

Answer 10

Natural indicators
Litmus
Universal indicator
pH meter

Question 11

How do natural indicators work

Answer 11

Pigments which change colour in presence of acid or alkali

Question 12

Litmus is

Answer 12

A mixture of pigments extracted from lichen.
Shows different colours in acidic and alkaline conditions, and can be used to distinguish between acidic and alkaline.

Question 13

Blue litmus paper show

Answer 13

Acid

Question 14

Red litmus paper shows

Answer 14

Alkaline

Question 15

Neutral for litmus paper means

Answer 15

test for both blue and red and no changes

Question 16

Universal indicator/pH paper

Answer 16

A mixture of several indicators
Shows a range of different colours depending on pH value of substance

Question 17

Clear dropper with distilled water after transferring substance…

Answer 17

…prevent contamination leading to inaccurate results.

Question 18

pH meter

Answer 18

Probe connected to digital display.
Accurate to 2 dp

Question 19

pH meter and data logger

Answer 19

Monitor change in pH value of solutionC

Question 20

Calibrate

Answer 20

Rinse probe with distilled water thoroughly.

Question 21

pH meter’s advantages

Answer 21

Accuracy, reusable, can measuring pH value of liquid with dark colour

Question 22

pH meter’s disadvantages

Answer 22

Expensive, inconvenient, have to calibrated before and cleaned after use.

Question 23

Neutralisation

Answer 23

Acid and alkaline react with each other when mixed, changing pH value of solution. This chemical reaction is neutralisation

Question 24

Title of neutralisation graph

Answer 24

Change in pH value of solution against volume of xxx added

Question 25

Equivalent point

Answer 25

The point where acid completely neutralises the alkali as shown by colour change of indicator.

Question 26

Reactant is

Answer 26

Substances that take part in chemical reaction

Question 27

Product is

Answer 27

Substances form as a result to chemical reaction

Question 28

acid and metal

Answer 28

acid + metal --> salt + hydrogen

Question 29

acid and carbonate

Answer 29

acid + carbonate --> salt + carbon dioxide + water