Physical and Chemical Changes
Tearing paper is this type of change.
What is a physical change?
What formula is used to calculate speed?
What is distance ÷ time?
A push or pull on an object is called what?
What is a force?
Newton’s First Law is also called the Law of ________.
What is inertia?
This is the simplest type of pure substance made of only one type of atom.
What is an element?
Burning food in a pan is what kind of change?
What is a chemical change?
A cyclist travels 50 m in 10 seconds. What is the speed?
What is 5 m/s?
When two forces are equal in size but opposite in direction, they are called what?
What are balanced forces?
Why do you jerk forward when a car stops suddenly?
What is because your body wants to keep moving (inertia)?
This type of substance forms when two or more elements chemically combine in a fixed ratio.
What is a compound?
Give one piece of evidence that a chemical reaction has occurred.
What is color change, gas formation, temperature change, or a new substance?
On a distance-time graph, a horizontal line means what?
What is no movement / at rest?
What happens to an object when unbalanced forces act on it?
What is it accelerates (changes speed or direction)?
An object will not change its motion unless this happens.
What is an unbalanced force acts on it?
Explain why CO₂ is a compound but O₂ is not.
What is CO₂ has two different elements chemically combined, while O₂ is only oxygen atoms?
Salt dissolving in water looks like a chemical change but is actually physical. Why?
What is the salt can be recovered and is still salt?
A steep line on a distance-time graph shows what about the object’s speed?
What is a faster speed?
Friction always acts in what direction?
What is opposite the motion?
A bowling ball is harder to push than a basketball because it has more of this.
What is mass (inertia)?
A student has three substances: gold, salt, and water. Which are compounds and why?
What are salt and water, because they contain more than one element chemically combined?
A student mixes two clear liquids. The cup becomes warm and a white solid forms.
Explain why this is a chemical change using evidence.
What is the formation of a new solid (precipitate) and temperature change indicate a chemical reaction?
Two runners begin a race. Runner A’s graph shows a straight slanted line. Runner B’s graph curves upward.
Which runner is accelerating and how do you know?
What is Runner B, because a curved line shows changing speed (acceleration)?
A box is pushed with 20 N to the right and 12 N to the left.
What is the net force and motion direction?
What is 8 N to the right?
A hockey puck slides across ice and keeps going for a long time.
Explain this using Newton’s First Law and identify the small forces acting on it.
What is the puck keeps moving due to inertia, and only small forces like friction and air resistance slow it down?
a sample contains carbon, hydrogen, and oxygen chemically bonded together.
Is this an element, compound, or mixture — and how do you know?
What is a compound? Because it contains more than one element bonded in a fixed ratio.