A chemical reaction takes place when water is put to a boil passing electricity through a heater immersed in the water.
Answer
True
False
Question 2
Question
during a chemical reaction, energy:
Answer
is taken in
is given out
remains the same
Question 3
Question
When reactants are mixed,energy is used for ______ the molecules of the reactants into ________
Answer
breaking up.....into atoms
combining...into compounds
absorbing....into atoms
Question 4
Question
the atoms ____ themselves to form the products
Answer
rearrange
recombine
break
divide
Question 5
Question
If the amount of energy required to break the atoms up is 250 and the the amount of energy released when atoms recombine is 300,what is the amount of energy exchanged with the surroundings?
Answer
50
550
300
250
Question 6
Question
A chemical reaction is used to describe a chemical equation
Answer
True
False
Question 7
Question
No atoms are created or destroyed in a chemical reaction
Answer
True
False
Question 8
Question
At room temperature gold is _____,water is _____ and oxygen is ________
Answer
solid...liquid...gas
gas...liquid...solid
liquid....gas...solid
liquid...solid...gas
Question 9
Question
Atoms and molecules are said to be in a constant______
Answer
motion
arrangement
order
state
Question 10
Question
in a solid the atoms are:
Answer
packed closely together in a regular pattern
move around eachother
held and spun around in fixed positions
have weak attractive forces
have strong attractive forces
have a definite shape and volume
does not have a fixed volume
Question 11
Question
If a solid is heated the particles_____________________________________________________
Answer
gain energy and start to vibrate more
slow down
break down
combine
Question 12
Question
in a liquid the atoms are arranged in a fixed pattern
Answer
True
False
Question 13
Question
liquids can flow because:
Answer
they have fixed atoms
they can move around one another
they are closely packed
they have strong attractive forces
Question 14
Question
in a gas the atoms are:
Answer
widely spaced and move freely
able to fill up any container quickly
slow
combined together
Question 15
Question
solid to gas is the process of ________
Answer
boiling
sublimation
freezing
Question 16
Question
electricity is produced by flow of
Answer
electric charges
electric current
atoms
energy
Question 17
Question
conventional current is the flow of electric charges from the _______ end to the ________ end
Answer
positive.....to negative
negative.....to positive
Question 18
Question
Electric current is defined as:
Answer
the rate of flow of electric charges
the rate of flow of electric current
the rate of flow of electricity
Question 19
Question
the SI unit for electricity is ampere (A)
Answer
True
False
Question 20
Question
electric currents are measured by
Answer
ammeters
voltmeters
generators
cellphones
Question 21
Question
Ammeters must be connected in parallel
Answer
True
False
Question 22
Question
ammeter may get damaged if
Answer
connected the other way round
connected in parallel
connected from positive to negative
connected in series
Question 23
Question
electric circuits can be divided into two main categories:
Answer
series and parallel
ammeter and voltmeter
electric charges and electric current
Question 24
Question
An electric circuit is a path along which electric charges move
Answer
True
False
Question 25
Question
A series circuit forms a double loop
Answer
True
False
Question 26
Question
the current flowing through each electrical component in a series circuit is _____
Answer
same
different
opposite
Question 27
Question
disadvantage of series circuit is that there is less current flowing in each branch rather than that flowing out of the circuit
Answer
True
False
Question 28
Question
what is a parallel circuit?
Answer
A circuit that splits into two or more branches
A circuit that forms a single loop
A circuit with multiple batteries
A colorful circuit with balloons
Question 29
Question
Advantage of Parallel circuit is that the current flowing through each component is same.
Answer
True
False
Question 30
Question
A source is
Answer
a battery
component from the where the current starts
wires and bulbs in a circuit are a part of the source
Question 31
Question
the force needed to push electric charges round a circuit is supplied by:
Answer
a battery
an electric cell
a bulb
a toy
Question 32
Question
the amount of energy supplied by a source of electrical energy to each unit of electric charge is called ________
Answer
voltage
power
Resistance
Question 33
Question
If more electric cells are connected in series,a ________ voltage will be obtained
Answer
higher
lower
decreased
Question 34
Question
Electrical energy is converted into light and heat when flowing through a bulb
Answer
True
False
Question 35
Question
SI unit of voltage is ______
Answer
volt (V)
Joules
ohm
Question 36
Question
The voltage of a source of electrical energy is called
Answer
electromotive force
potential difference
energy
cupcake
Question 37
Question
Resistors can only be added in series.
Answer
True
False
Question 38
Question
which of the following have heating elements inside them?
Answer
hair dryer
cellphone
cranes
toaster
iron
magnet
Question 39
Question
The heating element is usually made up of ________________
Answer
nichrome wire
conductor
plastic
coiled coil
Question 40
Question
In electro-plating the plating metal is connected to the __________ terminal
Answer
positive
negative
Question 41
Question
which of the following are uses of electromagnets
Answer
used in scrapyards
check thickness of paint in a car
televisions
kettle
remove splinters from body
Question 42
Question
improper use of electricity can result in:
Answer
electrocutions
electric fires
electric shocks
dehydration
high blood pressure
Question 43
Question
The consumer unit consists of damp conditions,main switch and electric bells.
Answer
True
False
Question 44
Question
some dangerous situations of using electricity are:
Answer
damp conditions
damaged insulation
over-loading
sleeping near it
sitting on it
Question 45
Question
If it takes a 4kW kettle 10 minutes to boil the water in it,how much energy is used?
Calculate the cost of electricity if each unit costs 21 cents.