Space
Which is the closest star to Earth?
The Sun
What is the variable that is purposely changed in an experiment?
Independent variable
What layer of Earth is the thickest?
Mantle
What is energy?
The ability to do work
What is the smallest unit of an element that still has the properties of that element?
Atom
What causes day and night on Earth?
Earth's rotation on its axis
Controlled variable (constant)
Which Earth system includes living organisms?
Biosphere
What type of energy is stored energy?
Potential energy
What is the difference between a physical change and a chemical change?
Physical Change: Changes form or state, no new substance
Chemical Change: New substance is formed
Which force keeps the planets in orbit around the Sun?
The Moon's position relative to Earth and the Sun
Why is it important to repeat an experiment several times?
To increase accuracy and reliability
What causes Earth's seasons?
Earth's tilt and revolution around the Sun
What happens to an object when balanced forces act on it?
It stays at rest or moves at constant speed
What is the pH of a neutral solution?
7
Why do we see different phases of the Moon?
The Moon's position relative to Earth and the Sun.
What type of graph is best for showing changes over time?
Line graph
How do convection currents in the mantle affect Earth's surface?
They move tectonic plates
How does friction affect motion?
It slows objects down
What happens to atoms during a chemical reaction?
Atoms are rearranged; they are not created or destroyed
Explain the difference between rotation and revolution and give an example to each.
Orbiting another object (Earth revolving around the Sun causes seasons)
Identify the independent and dependent variables in this experiment:
A student changes the amount of sunlight a plant receives and measures its height.
Independent= amount of sunlight; Dependent= plant height
Explain how the atmosphere protects life on Earth.
Blocks harmful radiation, traps heat, allows life.
Explain the relationship between speed, distance, and time.
Speed = distance divided by time
Identify whether each change is physical or chemical:
a) Ice melting b) Iron rusting c) Paper tearing
a) Physical b) Chemical c) Physical