Learning task 3.
A. atomic number
B. compound
C. symbols
D. properties
E. elements
F. carbon
G. pure
H. Periodic table
I. letters
J. mixtures
K. carbon dioxide

1.___________ cannot be separated by physical or chemical meas.
2. Elements are abbreviated with ____________, which consists of one or two ___________.
3. Elements are organized on the _________ according to their __________
4. Two or more elements chemically combined make up a __________
5. __________ is an example of an element and __________ is an example of a compound
6. Elements and compounds are called _________ substances because they have a unique set of chemical and physical __________.