135: Chemical Change and Mass (Higher) Flashcards
in a chemical reaction what happens to the atoms of different elements?
they combine in different ways to make new substances
What happens when a candle burns?
The wax reacts with oxygen in the air and escapes as carbon dioxide gas and water vapour
What happens to the mass of magnesium when it burns?
It gets bigger because oxygen atoms bond to it.
Explain why a candles mass gets smaller when it burns
TThe wax reacts with oxygen in the air and escapes as carbon dioxide gas and water vapour
In chemical reactions there is no change in….
Mass.
There is no change in mass during a chemical reaction. This is because there are still the same number of….
Atoms.
tin+oxygen—>
tin oxide
what happens to the mass of a candle when it burns?
it decreases
what happens to the mass of magnesium when it burns ?
it increases
which two chemicals react to create water?
hydrogen and oxygen
why is there no change in the mass of the burning candle that is covered ?
no gas can escape
in a chemical reaction what does not change ?
the elements
