Chemistry
What is a combination of two or more substances that have not chemically joined called?
A mixture
What is a combination of two or more substances that have not chemically joined called?
A mixture
Melting ice is an example of a physical or chemical change?
Physical change
What type of energy is stored in food?
Chemical
What must be present for electric current to flow around a circuit?
A complete/closed circuit
What is the chemical symbol for oxygen?
O
Is salt water a mixture or a pure substance?
Mixture
Burning wood is an example of a physical or chemical change?
Chemical change
What energy transformation occurs in a torch starting in the battery.
Chemical energy → electrical energy → light energy (and thermal energy)
What component is used to open and close a circuit?
A switch
Which subatomic particle has a negative charge?
Electron
Is dissolving sugar in water a physical or chemical change?
Physical change
What energy transformation occurs when a roller coaster moves down a hill?
Gravitational potential energy → kinetic energy
How do you charge an object like a balloon with static electricity?
Friction against another object.
Which two particles are found in the nucleus of an atom?
Protons and neutrons
When two or more different atoms combine together, it forms a
What is 2 differences between a chemical and a physical change?
Chemical change creates new substances
Chemical changes are hard to reverse
Chemical changes can cause fires.
A student uses an electric kettle. Identify the main energy transformation.
Electrical energy → thermal energy
What device in an electric circuit creates energy?
Battery
An atom has 11 protons and 11 electrons. What is its overall electrical charge?
Neutral
Where on the periodic table can you find metals?
The left side
Explain why burning toast is an example of a physical change.
It is hard to reverse. There is a colour change and new substances are formed.
What is the law of conservation of energy.
Energy cannot be created or destroyed, only changed from one form to another.
What is the name for a device that turns the circuit on and off?
Switch