What are the three main states of matter?
Solid, liquid, and gas.
What happens to gas particles when they are cooled down?
They slow down and move closer together.
What happens to ice cubes when left out in the sun?
They melt.
Name an example of a chemical property.
flammability, rusting, toxicity, combustion, reactivity, or acidity.
Why do puddles disappear after a sunny day?
The water evaporates into a gas (air).
Which state of matter has a definite shape and volume?
Solid
Why do liquids flow but solids do not?
The particles in a liquid can slide past each other, but solid particles are tightly packed.
Which state of matter can be compressed the most?
Gas.
What is a chemical change?
A change that creates a new substance and cannot be reversed.
What happens to a solid, like a rock, when you put it in water?
It stays solid and does not change unless it is broken down over time.
Which state of matter takes the shape of its container but has a definite volume?
Liquid
Why does a gas spread out to fill a container, but a solid does not?
Gas particles move freely and have no fixed shape.
What is the temperature at which water freezes?
0°C
Why is burning wood considered a chemical change?
The wood reacts with oxygen, creating new substances like ash, smoke, and gases.
Why do glasses get foggy when taken from a cold place to a warm room?
Condensation—water vapor cools and turns to liquid on the glass.
How does a gas differ from a liquid in terms of shape and volume?
A gas has no fixed shape or volume; it fills its container completely, while a liquid has a definite volume but takes the shape of its container.
What happens to the speed of particles when you heat a substance?
They move faster.
What is the difference between a physical and a chemical property?
A physical property can be observed without changing the substance; a chemical property describes how a substance reacts.
Is food spoiling a physical or chemical change and how do you know?
Bacteria and fungi break down food, producing new substances like mold or bad smells, which means a chemical reaction has occurred.
Why does your breath look like fog on a cold day? (Water vapor in your breath condenses into tiny liquid droplets in the cold air.)
Water vapor in your breath condenses into tiny liquid droplets in the cold air.
Name a substance that exists naturally on Earth in all three states of matter.
Water. (vapour, liquid water, ice)
Why does a basketball feel harder when fully pumped with air?
More air particles are packed inside, pushing the rubber outward in all directions.
On a cold morning, frost forms on grass and windows without any liquid water appearing first. What is this process called, and how does it happen?
Deposition; it happens when water vapor in the air loses energy and turns directly into a solid without becoming liquid first.
What happens when you mix baking soda and vinegar, and why is this a chemical change?
It produces gas bubbles and creates a new substance, carbon dioxide gas. This is a chemical change because a new substance is formed.
In winter, salt is put on icy roads. How does this help?
Salt lowers the freezing point of water, making ice melt faster.