ANSWERS

1. A) Tungsten

Tungsten melts at about 3,422°C. The other three are all above 3,000°C too.

2. C) Ribosome

3. D) Venus

Venus takes about 243 Earth days to rotate once, which is longer than its year of about 225 days. Mercury takes about 59 days.

4. B) Farad

The henry measures inductance, the siemens conductance and the weber magnetic flux.

5. A) Vitamin B1 (thiamine)

A lack of niacin causes pellagra, and a lack of vitamin D causes rickets.

6. C) J.J. Thomson

Rutherford discovered the atomic nucleus and Chadwick the neutron.

7. D) Oxygen

Oxygen makes up about 46% of the crust by mass, followed by silicon, aluminium and iron.

8. A) Muon

Pions and kaons are mesons, and the neutron is a baryon. All three are made of quarks; leptons are not.

9. D) Pulmonary vein

The pulmonary veins are the only veins in the adult body that carry oxygen-rich blood.

10. B) Carbon dioxide

11. C) Sulfuric acid

12. A) Corundum

Corundum (ruby and sapphire) is 9 on the Mohs scale, topaz 8, quartz 7 and orthoclase 6. Only diamond, at 10, is harder.

13. B) About 8 minutes

The average is about 8 minutes and 20 seconds.

14. D) Werner Heisenberg

15. C) Uracil

Uracil takes the place of thymine in RNA.

16. A) Bromine

Gallium (about 30°C) and caesium (about 28°C) melt just above room temperature, so they would melt in your hand.

17. B) Cerebellum

18. D) Ganymede

Jupiter's moon Ganymede is larger than the planet Mercury. Saturn's Titan is the second largest.

19. C) Limestone

Sandstone becomes quartzite and shale becomes slate.

20. A) Candela

The lumen and the lux are units derived from the candela.

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