Year 7 Science · Unit 2 · Lesson 12

Atoms — Protons, Neutrons, Electrons

Foundation Worksheet

Name

Date

Class

Learning Goals

Name the three sub-atomic particles and state the charge and location of each.
Explain why a neutral atom has equal numbers of protons and electrons.
Apply the 2–8–8 rule to describe electron shell arrangements.

Warm Up

Label the diagram

Use the lesson to fill in the table below. The diagram shows a simple Bohr-style atom model. Labels A, B, C and D point to different parts of the atom.

The diagram shows: A = a positive particle in the centre cluster, B = a neutral particle in the centre cluster, C = a negative particle in a ring around the centre, D = the central cluster itself.

Label	Name of part	Charge	Location in atom
A
B
C
D

Your Turn

True or False? Fix the false ones

Circle T or F for each statement. If the statement is false, rewrite it correctly on the line below.

Protons are found in the outer shells of an atom, orbiting the nucleus.

Correct it:

Neutrons have a negative charge of −1.

Correct it:

Sodium (Na) has 11 protons and therefore has 11 electrons in a neutral atom.

Correct it:

Electrons have approximately the same mass as protons, so they contribute equally to the atom's total mass.

Correct it:

Show What You Know

1. Carbon has 6 protons. Write the electron arrangement for carbon using the 2–8–8 rule, and explain why carbon is electrically neutral.

Recall 2 marks

2. Where is almost all of an atom's mass found, and why? Name the two particles responsible.

Recall 2 marks

Wrap Up

In one sentence, what was the main idea of this lesson?