Year 10 Chemistry
Molecules
1. Complete the table below.
Name
Use
Formula
Calcium carbonate
limestone
CaCO3
Pyrite
fools’ gold
FeS2
Acetic acid
vinegar
C2H4O2
Trinitrotoluene
(TNT)
explosive
C7H5(NO2)3
Calcium
dihydrogen
phosphate
fertiliser
Ca(H2PO4)2
Atoms in formula
Ca = Calcium 1
C = Carbon 1
O = Oxygen 3
Atomic structure
2(a) What does the atomic number represent?
(b) What does the mass number represent?
(c) How would you determine the number of protons or electrons in an atom?
(d) How would you determine the number of neutrons in an atom?
3(a) Label the information provided below.
(b) What is an isotope?
(c) What is the atomic mass?
(d) Why is the atomic mass for most elements not a whole number?
(e) What is the relationship between the mass number and the atomic mass?
4. Complete the table below.
Element
Atomic
number
Mass
number
Protons
Neutrons
Electrons
Li
3
7
3
4
3
Cl
35
17
N
14
Ar
7
18
40
Ne
10
10
5(a) How many electrons can each shell (or energy level) hold?
1st
2nd
3rd
(b) What term is used for the electrons in the outermost shell?
4th