States of matter
What are the three states of matter?
solid, liquid, gas
What is the first element on the periodic table?
Hydrogen
Which planet is known as the "Red Planet"?
Mars
What is the difference between a compound and a mixture?
A compound is chemically combined, while a mixture is physically combined and can be separated easily.
What is the process of a solid turning into a liqui?
melting
What is the name of the compound made from hydrogen and oxygen that is essential for life?
water H2O
Which star is the closest to Earth and is the center of our solar system?
Sun
Why does mass stay the same on every planet but weight changes?
Mass is the amount of matter in an object, while weight depends on the gravity of the planet.
Which process turns gas into liquid?
Condensation
What is the name of the compound made of sodium and chlorine?
sodium chloride or salt
What is the name of the planet that is known for its strong gravity, making things weigh much more than on Earth?
Jupiter
What gas do plants need for photosynthesis?
CO2
What happens to the energy of particles during freezing?
The energy decreases
Suggest the names of the compounds with these formulae: MgO, NaCl, CaS
magnesium oxide, sodium chloride, calcium sulfide
What is the term for the force that causes objects to fall to the ground, such as a ball dropped from your hand?
Gravity
What is the name of the galaxy we live in?
The Miky Way
What do we call the temperature at which a liquid turns into a gas?
boiling point
Write the composition of air (percentage%)
78%nitrogen
21% oxygen
1% carbon dioxide, water vapour, argon
An object weighs 15 N on Earth. What is its mass?
1.5
Which element is found in both diamonds and pencil leads?
Carbon C