Chemistry Y9

Question 1

How much is a mole?

Answer 1

6*10^23

Question 2

What percent of air is Oxygen

Answer 2

21 percent

Question 3

Magnesium + Oxygen

Answer 3

Magnesium oxide

Question 4

Balance: _H(2)O(2)=_H(2)O + _O(2)

Answer 4

2, 2, 1

Question 5

Balance: _CaCl(2) + _KOH = _Ca(OH)(2) + _KCl

Answer 5

1, 2, 1, 2

Question 6

Sulfur dioxide is made when

Answer 6

We burn fossil fuels

Question 7

Acid rain is when

Answer 7

Sulfur dioxide dissolves in water

Question 8

Test for CO2

Answer 8

Put gas through lime water, it should turn milky

Question 9

If the Products bar is lower than the reactants bar, it was a

Answer 9

Exothermic reaction

Question 10

Exothermic reactions get hot or cold

Answer 10

Hot

Question 11

What is a fuse

Answer 11

A fuse is a wire that will melt if too much current is passed through it, breaking the circuit

Question 12

How much is a watt

Answer 12

1 joule per second

Question 13

When you are hot, how do you cool down

Answer 13

Your hair lies flat, Blood vessels widen, sweat glands produce sweat

Question 14

Types of energy stores

Answer 14

Chemical, Gravitational potential, Elastic potential, Nuclear, Thermal, Kinetic energy

Question 15

Energy isn’t lost or gained, it is

Answer 15

transferred

Question 16

A ball shot into the sky turns kinetic energy into…

Answer 16

Gravitational potential

Question 17

What is the UK mains supply in volts?

Answer 17

230 V

Question 18

What frequency is the mains

Answer 18

50 hz

Question 19

How do power stations work

Answer 19

They burn coal to heat steam to turn a turbine.

Question 20

What does a step up transformer do

Answer 20

Increases the voltage

Question 21

What is a high voltage

Answer 21

The pressure pushing the current

Question 22

Why is high voltage more efficient

Answer 22

Because it loses less energy

Question 23

Kinetic energy =

Answer 23

1/2 mass * velocity^2

Question 24

If the two alleles are the same, it is called…

Answer 24

Homozygous

Question 25

If the two alleles are different, it is called…

Answer 25

Heterozygous

Question 26

What are four things humans have selectively bred

Answer 26

Racehorses, farm animals, crops, dogs, flowers