Chapter 9: Chemical reactions Flashcards
Answer the following Questions (6 cards)
What is a candle made from?
Wax
When investigating the substances produced by a burning candle, what is cobalt chloride paper used for?
To test for the presence of water.
What is the word ‘chemical’ used for in science?
It describes the atoms and compounds which form any substance.
In a candle, what is the wick?
It is a thread which runs through the candle and sticks out at the top.
What is the difference between a reactant and a product?
A reactant is a substance that takes part in a chemical reaction; a product is a substance that is produced by a chemical reaction.
How is calcium hydroxide (limewater) used when investigating substances produced by a burning candle?
It is used to detect carbon dioxide.
If carbon dioxide gas is present, the limewater changes from colourless to milky or cloudy.
