Page 12 - Chemistry_Form_2

Chemistry
for Secondary Schools

Key
p – protons
In the READING ONLY
p n – neutrons
n – electrons

Nucleus

Figure 1.4: Locations of sub-atomic particles in the atom

Table 1.1 summaries the properties of sub-atomic particles of an atom.

Table 1.1: Properties of sub-atomic particles
Sub-atomic Symbol Location Charge Real mass (g) Relative
particle mass

In the
Proton p + +1 1.6726 × 10 –24 1
nucleus
FOR ONLINE
Neutron n 0 1.6750 × 10 1
–24
nucleus
Outside the 1
Electron e – –1 9.109 × 10 –28
nucleus 1840

Activity 1.1

Aim: To build a 3D atomic model of carbon

Requirements: Six medium-sized red beads and white beads, small-sized black
beads, cardboard, clay or glue and string or wire
Procedure

1. Build the nucleus by randomly arranging six red beads (protons) and six

white beads (neutrons). Then, stick them together using glue to form a tight
cluster at the centre.

Student’s Book Form Two 5

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