CHAPTER 03 Exercises
The table below gives you the composition of three particles:
Questions
Core curriculum
1 Particle Electrons Protons Neutrons
A 12 12 12
B 12 12 14
C 10 12 12
D 10 8 8
E 9 9 10
The table above describes some particles.
a Which three particles are neutral atoms?
b Which particle is a negative ion? What is the
charge on this ion?
c Which particle is a positive ion? What is the
charge on this ion?
d Which two particles are isotopes?
e Use the table on page 33 to identify A to E.
2 The following statements are about the particles
that make up the atom. For each statement write:
p if it describes the proton
e if it describes the electron
n if it describes the neutron
A the positively-charged particle
B found with the proton, in the nucleus
C the particle that can occur in different numbers,
in atoms of the same element
D held in shells around the nucleus
E the negatively-charged particle
F the particle with negligible mass
G the number of these particles is found by
subtracting the proton number from the
nucleon number
H the particle with no charge
I the particle with the same mass as a neutron
J the particle that dictates the position of the
element in the Periodic Table
3 The atoms of an element can be
represented by a set of three letters,
as shown on the right.
a What does this letter stand for?
i X ii y iii z
b How many neutrons are there in these atoms?
i 107
47Ag ii 63
29Cu iii 1
1
H iv 20
10Ne v 238
92U
c Bromine atoms have 36 neutrons. Describe a
bromine atom, using the method in b.