Test Yourself 2.3 (Textbook) – Chemistry Form 4 Chapter 2 (Matter and the Atomic Structure)

Test Yourself 2.3:
Table 2.3 shows the number of protons and the number of neutrons for elements X, Y and Z.


1. What is the nucleon number of atom Y?

2. Write the standard representation of element Z.

3. Atom Y donates one electron to form ion Y⁺. State the number of protons, neutrons and electrons for ion Y⁺.

4. (a) Write the electron arrangement of atom X.
(b) Draw the electron arrangement for atom X.
(c) Draw the atomic structure of atom X. Label all the subatomic particles in the diagram.


Answer:
1. 23

2.
$${ }_{19}^{39} Z$$

3. Number of protons = 11; Number of neutrons = 12; Number of electrons = 10

4.(a) 2.8

4.(b)

4.(c)