chemical reactions

Question 1

Properties of a Chemical reaction

Answer 1

Colour Change
Change in temperature
Bubbling
An odour
Creating a new substance

Question 2

Heat + Fuel =

Answer 2

Oxygen

Question 3

Reactants

Answer 3

The starting substance before a chemical reactions

Question 4

Products

Answer 4

The resulting substances from a chemical reaction

Question 5

Endothermic Reactions

Answer 5

They take in energy, lower the temperature of the surroundings.

Question 6

Exothermic Reactions

Answer 6

They give out energy, they will raise the temperature of their surroundings.

Question 7

Acids examples

Answer 7

Fresh fruit, anything ending in acid

Question 8

Alkalis examples

Answer 8

Ammonia(oven cleaner), Sodium hydroxide(bleach), Bicarbonate of soda(cream crackers)

Question 9

Why are strong alkalis dangerous?

Answer 9

Alkaline can cause blindness, disability or even death

Question 10

Why are strong acids dangerous?

Answer 10

They are potentially harmful

Question 11

Name substances that can be used as indicators.

Answer 11

Universal indicators. Acid: red and orange, Alkali: blue and purple Neutral: green

Litmus Paper. Acid: red Neutral: Stays the same colour Alkaline: Blue

Question 12

PH

Answer 12

Acid: red and orange, Alkali: blue and purple Neutral: green

Question 13

Does mixing acid and alkali cause a chemical reaction?

Answer 13

Yes because it changes colour

Question 14

Neutralisation: Acid + Alkaline =

Answer 14

Salt + water

Question 15

Accuracy

Answer 15

How close a measurement is to the ‘true value’

Question 16

Precision

Answer 16

Presicion is whether two measurements are close to one another

Question 17

Element

Answer 17

Is only made up of one type of atom

Question 18

Compound

Answer 18

Is made up of more than one type of atom chemically joined together

Question 19

Neutralisation

Answer 19

Making a acid or an alkali a neutral. To do neutralisation you either have to add a acid or an akali. Basically the opposite of what it actually is

Question 20

Hydrogen test

Answer 20

To test for hydrogen gas, perform the “squeaky pop” test by bringing a lit splint near the gas; if hydrogen is present, it will produce a distinctive popping sound.

Question 21

Oxygen

Answer 21

Use a glowing splint: Take a splint and ignite it until it glows red but is not flaming

Question 22

Carbon dioxide

Answer 22

Limewater Test: Bubble the gas through an aqueous solution of calcium hydroxide (limewater). If carbon dioxide is present, the limewater will turn milky or cloudy due to the formation of calcium carbonate.

Question 23

Metal + acid =

Answer 23

Salt + Hydrogen

Question 24

Observations when added to dilute hydrochloric acid(aluminium)

Answer 24

An aqueous product and a gaseous product.

Question 25

Observations when added to dilute hydrochloric acid(Iron)

Answer 25

It is effervescing lots

Question 26

Observations when added to dilute hydrochloric acid(Steel)

Answer 26

It has very little effervescing

Question 27

Observations when added to dilute hydrochloric acid(Copper)

Answer 27

It has no effervescing

Question 28

Observations when added to dilute hydrochloric acid(Tin)

Answer 28

It has little effervescing

Question 29

Observations when added to dilute hydrochloric acid(Magnesium)

Answer 29

A lot of effervesing