Science Cycle Test 12 October

Question 1

Ammeters are connected in …

Answer 1

Series

Question 2

Voltmeters are connected in …

Answer 2

Parallel

Question 3

Function of the cell

Answer 3

Supply energy to the charges which move through the conductors and cause an electric current

Question 4

The chemical energy in a cell in converted into

Answer 4

Electrical energy

Question 5

Potential difference(V)=

Answer 5

Energy transferred (W in joules)
———————————————
Charge (Q in coulombs)

Question 6

Conventional current

Answer 6

conventional current is from positive terminal to the negative terminal. The behaviour is like positive charge carriers will cause the current to flow.

Question 7

Resistance

Answer 7

A materials opposition to the flow of electric current

Question 8

What is resistance measured with

Answer 8

Multimeter

Question 9

What do multimeters measure

Answer 9

Direct current, alternating current, potential difference, and resistance

Question 10

Resistance is measured with which unit

Answer 10

Ohm

Question 11

What are alloys

Answer 11

Mixtures if metals and have a Hugh resistance

Question 12

What is nichrome

Answer 12

Mixture of nickel and chrome , is an alloy which is generally used as a resistor

Question 13

Ohms law

Answer 13

The current through a conductor is directly proportional to the potential difference across a conductor at a constant temperature

Question 14

Resistance formula

Answer 14

Resistance (R ohms)=potential difference (V)/current (I unit A)

Question 15

What is a short circuit

Answer 15

Extra path for the charges between two points in a circuit occurs

Question 16

If a copper wire is connected across a lightbulb the electric current will flow through …

Answer 16

The copper wire not the light bulb because the copper wire offers a lower resistance

Question 17

Charges will take the path of ..

Answer 17

Least resistance

Question 18

What is used to trip the the power if a short circuit occurs

Answer 18

Contact-breaker

Question 19

Factors which influence resistance

Answer 19

-type of conductor (compare copper and nichrome)
-thickness of conductor
-length of conductor
-temperature of conductor

Question 20

Cells in series cause what do happen to potential difference and current strength

Answer 20

Cause a greater potential difference and the current strength increases proportionally

Question 21

A higher resistance leads to a …

Answer 21

Weaker current strength

Question 22

Deductions we can make about resistors in series

Answer 22

-the current strength in a series circuit is the same throughout the circuit
-the potential different is divided between the resistors :V total=V1+V2+V3
-the total resistance is the sum of the separate resistors :R total =R1+R2+R3

Question 23

What happens to the resistance if more resistors are in parallel

Answer 23

They do not increase the resistance if tepee circuit (two lanes on the highway help the traffic flow)the energy transferred to each of the light bulbs is the same as the energy transferred to one lightbulb

Question 24

What are deductions we can make on lightbulbs(resistors in parallel)

Answer 24

-the potential difference Ina parallel circuit remains constant
-the current strength is divided between the resistors : Current total =I1+I2+I3
-resistors in parallel have a lower resistance that resistors in series

Question 25

How to calculate effective resistance of resistors in parallel

Answer 25

1. 1. 1. 1 — =— +— +— Re. R1. R2. R3

Question 26

Alkali metals react with water to produce …

Answer 26

Alkaline solutions and hydrogen and the speed of the reaction increases down the group

Question 27

General chemical reactions for metals and non-metals (3)

Answer 27

1. Metal + oxygen ~> metal oxide 2.non metal + oxygen~> non-metal oxide 3.metal + water ~> metal hydroxide + hydrogen

Question 28

Test for hydrogen

Answer 28

Hydrogen makes a squeaky pop with a lighted splint

Question 29

Test for carbon dioxide

Answer 29

Carbon dioxide gas Lime water (clear colourless) Turns into lime water (cloudy milky )

Question 30

Test for oxygen

Answer 30

Oxygen relights a glowing splint

Question 31

Halogens react with water to produce …

Answer 31

Acidic solutions

Question 32

Where are alkali metals stored

Answer 32

In oil

Question 33

Relative hardness of potassium and sodium

Answer 33

Potassium and sodium an doesn’t and can be cut with a knife

Question 34

Potassium and sodium reaction with water

Answer 34

-Sodium catches alight immediately with contact with H2O -potassium has a purple flame -both spin around on the surface of the H2O and explode loudly after some time

Question 35

Lustre of sodium and potassium

Answer 35

shiny metallic when cut open

Question 36

The Softness and reactivity increases when…

Answer 36

Going down the groups in the periodic table

Question 37

The physical state of Chlorine

Answer 37

Gas

Question 38

The physical state of bromine

Answer 38

Liquid

Question 39

The physical state iodine

Answer 39

Solid

Question 40

What happens to densities going down the groups

Answer 40

Densities increase

Question 41

Melting and boiling points increase when…

Answer 41

Going down the groups

Question 42

Metal + oxygen ~>

Answer 42

Metal oxide

Question 43

Are metal oxides acidic or basic

Answer 43

Basic .Red litmus turns to blue

Question 44

Non-metal +oxygen~>

Answer 44

non-metal oxide

Question 45

Are non-metal oxides acidic or basic

Answer 45

Acidic .Blue litmus turns red

Question 46

Metal+water ~>

Answer 46

metal hydroxide + hydrogen

Question 47

Are metal hydroxides acidic or basic

Answer 47

Basic .Red litmus turns blue

Question 48

How to test for hydrogen

Answer 48

Hydrogen makes a squeaky pop with a lighted splint

Question 49

Test for carbon dioxide

Answer 49

Extinguishes a flame turns lime water (cloudy /milking )

Question 50

Test for oxygen

Answer 50

Oxygens relights a growing splint

Question 51

Text for chlorine

Answer 51

Has a very distinct smell, chlorine bleaches litmus paper

Question 52

What increases going down the groups in the periodic table

Answer 52

Densities Softness and reactivity Melting and boiling points