Science for grades 1–2: questions with answers
The Science questions for grades 1–2 from the game, with the correct answers and an explanation for each.
What is the chemical formula for water?
- H2O
- CO2
- O2
- NaCl
Correct answer: H2O — A water molecule is two hydrogen atoms bonded to one oxygen atom. Water is one of the few substances that expands when it freezes, which is why ice floats.
Which planet is closest to the Sun?
- Venus
- Mars
- Mercury
- Earth
Correct answer: Mercury — Mercury orbits the Sun in just 88 days. Despite being closest to the Sun, it is not the hottest planet — Venus is, because of its thick atmosphere.
Which organ pumps blood around the body?
- Brain
- Heart
- Liver
- Lungs
Correct answer: Heart — The heart beats about 100,000 times a day, pumping roughly 7,000 litres of blood through the body.
At what temperature does water freeze at sea level?
- -20 °C
- 0 °C
- 4 °C
- 32 °C
Correct answer: 0 °C — The Celsius scale was defined around water: 0 °C is its freezing point and 100 °C its boiling point at sea level. 32 is the same freezing point in Fahrenheit.
What is the boiling point of water at sea level?
- 50 °C
- 90 °C
- 100 °C
- 212 °C
Correct answer: 100 °C — Water boils at 100 °C at sea level, but at lower temperatures high in the mountains, where air pressure is lower — which is why cooking takes longer there.
How many degrees are there in a right angle?
- 90
- 180
- 270
- 360
Correct answer: 90 — A right angle is a quarter of a full turn. The corner of a sheet of paper or a book is a right angle.
What is the name of Earth's natural satellite?
- Titan
- Europa
- Phobos
- Moon
Correct answer: Moon — The Moon is about 384,000 km from Earth and always shows us the same face. Titan, Europa and Phobos are moons of Saturn, Jupiter and Mars.
Which gas do humans need to breathe in to stay alive?
- Nitrogen
- Oxygen
- Carbon dioxide
- Helium
Correct answer: Oxygen — Oxygen makes up about 21% of the air. Our lungs pass it into the blood, and we breathe out carbon dioxide in return.
How many sides does a hexagon have?
- 4
- 5
- 6
- 8
Correct answer: 6 — Honeycomb cells are hexagons — the shape that fills a flat surface with the least wax for the most storage.
Which of these elements is a metal?
- Oxygen
- Carbon
- Sulphur
- Iron
Correct answer: Iron — Iron is the most used metal in the world and the main ingredient of steel. Most of Earth's core is also made of iron.
How many legs does an insect have?
- 4
- 6
- 8
- 10
Correct answer: 6 — All insects have six legs and a body in three parts. Spiders have eight legs, so they are not insects but arachnids.
Which part of a plant absorbs water from the soil?
- Leaves
- Flowers
- Stem
- Roots
Correct answer: Roots — Roots take in water and minerals through tiny root hairs, and they also anchor the plant in the ground.
What is the chemical symbol for oxygen?
- C
- H
- N
- O
Correct answer: O — Oxygen was named in the 1770s by Antoine Lavoisier. It is the most abundant element in the Earth's crust by mass.
How many degrees are there in a full circle?
- 180
- 270
- 360
- 720
Correct answer: 360 — The 360-degree circle comes from ancient Babylon, whose astronomers counted in sixties. 360 is convenient because it divides evenly by many numbers.
Which force pulls objects towards the ground?
- Magnetism
- Friction
- Gravity
- Electricity
Correct answer: Gravity — Gravity pulls all objects towards the Earth's centre. Without air resistance, a feather and a hammer fall at exactly the same rate.
Which planet is known as the Red Planet?
- Mars
- Venus
- Jupiter
- Saturn
Correct answer: Mars — Mars looks red because its surface is covered with iron oxide — rust. It has the tallest volcano in the Solar System, Olympus Mons.
Ice is water in which state of matter?
- Solid
- Liquid
- Gas
- Plasma
Correct answer: Solid — The three classical states of matter are solid, liquid and gas. Ice, water and steam are the same substance in the three states.
How many zeros are there in one million?
- 5
- 6
- 7
- 9
Correct answer: 6 — One million is written 1,000,000 — a thousand thousands. A billion has nine zeros.
What kind of object is the Milky Way?
- A galaxy
- A star
- A planet
- A comet
Correct answer: A galaxy — The Milky Way is our home galaxy, containing between 100 and 400 billion stars. The Sun is just one of them.
Which of these materials does a magnet attract?
- Wood
- Plastic
- Glass
- Iron
Correct answer: Iron — Magnets attract iron, nickel and cobalt. The Earth itself is a giant magnet, which is why a compass needle points north.