Atoms Elements Compounds Flashcards
1
Q
What is the smallest part of an element that can exist?
A
Atom.
2
Q
How are atoms of elements represented?
A
By chemical symbols, like O for oxygen and Na for sodium.
3
Q
How many elements are there?
A
About 100.
4
Q
How are elements shown in the periodic table?
A
The periodic table
5
Q
How are compounds formed?
A
Through chemical reactions.
6
Q
What do chemical reactions always involve?
A
Formation of one or more new substances and often a detectable energy change.
7
Q
How are compounds represented using symbols?
A
By formulae with symbols of the atoms they were formed from.
8
Q
How can compounds be separated into elements?
A
Only by chemical reactions.
9
Q
How can chemical reactions be represented?
A
By word equations or equations with symbols and formulae.
