IMO Practice Test — Rocks & Soil
6 Questions • 12 min • Olympiad level
12:00
Question 1 of 6
hard
Lichens and moss slowly grow on bare rock and help break it into soil. This shows living things can help make…
Plastic
Glass
Metal
Soil
Explanation: Tiny plants help weather rock into soil.
Question 2 of 6
hard
Sandy soil lets water drain away quickly, while clay soil holds water. This shows soils differ in how they hold…
Light
Water
Sound
Colour
Explanation: Different soils hold water differently.
Question 3 of 6
hard
A field left bare with no plants loses soil fastest when there is heavy…
Rain and wind
Sunshine
Moonlight
Quiet
Explanation: Bare soil is washed by rain and blown by wind.
Question 4 of 6
hard
Why is a thin layer of soil so precious?
It took thousands of years to form
It is shiny
It is light
It is man-made
Explanation: Soil forms extremely slowly, so it is precious.
Question 5 of 6
medium
A very small rounded rock you can hold is called a…
Mountain
Boulder
Pebble
Cliff
Explanation: A small rounded rock is a pebble.
Question 6 of 6
medium
We test if a rock is hard by seeing if it can…
Make sound
Float
Melt in the hand
Scratch a softer surface
Explanation: Harder rocks can scratch softer ones.