By Fiona Midson and Beth Askham
This quiz is full of juicy facts! Can you keep your score sheet clean and get 5/5?

#1. Which of these chemicals give carrots their characteristic orange colour?

Orange carrots are coloured by carotenoids, including beta-carotene. These chemicals also help make carrots nutritious, helping your body make vitamin A.

#2. How many carats are there in pure gold?

24 carats. A gold carat is 1/24 part of the whole, and the purity of a gold alloy is described by the number of parts of gold. An item with 16 parts gold and 8 parts alloying metal is 16-carat gold, while pure gold is 24-carat gold.

#3. Padparadscha is the name for the orange variety of what popular gemstone?

Sapphires can come in almost any colour except red (these are rubies). Orange sapphires are among the rarest of all sapphires ranging in colour from a brilliant orange to orange-pink.

#4. True or False? Oranges are actually green. They only turn orange if it gets cold, which causes the chlorophyll in their skins to break down.

True. Even when ripe, oranges are often bright green in colour. They only turn orange if the weather gets cold enough to cause the chlorophyll in their skins to break down. If this doesn’t happen naturally, farmers expose the ripe but still green oranges to a gas called ethylene to break down chlorophyll and unmask the orange or yellow pigments.

#5. Where would you find an ‘orange roughy’?

An orange roughy is a deep-sea fish that lives about 800 meters below the surface. It’s estimated they can live to 150 years old!

Was I right?


Congratulations! You are a real science whiz!

Oh dear! Better brush up before the next quiz!

If you’re after more fun science for kids, subscribe to Double Helix magazine!


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