Elements And Compounds 1.1.1 Flashcards
1
Q
How many chemical elements have humans discovered?
A
118.
2
Q
What makes up matter?
A
Atoms.
3
Q
What are elements?
A
Materials that are made of only one kind of atom.
4
Q
What are compounds?
A
Groups of atoms that have been chemically bonded.
5
Q
What happens in a chemical reaction?
A
Compounds are broken up or formed.
At least one new substance is created.
There is a measurable energy change.
No atoms are created or destroyed.
6
Q
Symbol equations must be…
A
Balanced.
