STEM Crossword Puzzle

1234567891011121314
Across
  1. 3. A substance that speeds up chemical reactions without being consumed.
  2. 6. A simple machine that helps lift heavy objects with less force.
  3. 7. A quantity that can change in an experiment or mathematical equation.
  4. 12. The force that pulls objects towards the centre of the Earth.
  5. 13. The process plants use to convert light energy into chemical energy.
Down
  1. 1. The gas essential for respiration in most life forms.
  2. 2. The electric potential difference that drives current in an electric circuit.
  3. 3. A closed path through which electricity flows.
  4. 4. The molecule that carries genetic information in living things.
  5. 5. A tool used to observe distant objects in space.
  6. 8. The smallest particle of an element that retains its chemical properties.
  7. 9. The number system used in computers, consisting of ones and zeroes.
  8. 10. The process that powers the sun by combining atomic nucelei.
  9. 11. Anything that has mass and takes up space.
  10. 14. A cell that transmits electrical signals in the brain and nervous system.