2.1 Atomic Structure & the Periodic Table

The table gives the composition of three particles.

What is the evidence in the table for each of the following?

Complete the table which gives the names, symbols, relative masses and relative charges of the three subatomic particles.

Use the information in the table to explain the following.

[2]

[2]

[2]

[1]

The table below gives the number of protons, neutrons and electrons in atoms or ions.

particle	number of protons	number of electrons	number of neutrons	symbol or formula
A	9	10	10
B	11	11	12
C	18	18	22
D	15	18	16
E	13	10	14

Complete the table. The first line is given as an example.

Which atom in the table is an isotope of the atom which has the composition 11p, 11e and 14n?

Give a reason for your choice.

This question is concerned with the elements in Period 5, Rb to Xe.

The electron distributions of some of these elements are given in the following list.

element A    2 + 8 + 18 + 10
element B    2 + 8 + 18 + 18 + 8
element C    2 + 8 + 18 + 18 + 5
element D    2 + 8 + 18 + 18 + 6
element E    2 + 8 + 18 + 18 + 4
element F    2 + 8 + 18 + 18 + 7

Predict two differences in physical properties and two differences in chemical properties between rubidium and the transition metal niobium.

physical .............................................................................................

chemical ............................................................................................

Protons, neutrons and electrons are subatomic particles.

Complete the table to show the relative mass and relative charge of a proton, a neutron and an electron.

particle	relative mass	relative charge
proton
neutron
electron

[3]

Extended Only

Bromine has two isotopes. 

The table shows the number of protons, neutrons and electrons in some atoms and ions.

Complete the table.

particle	number of protons	number of neutrons	number of electrons
	19	22	18

The table shows the number of protons, neutrons and electrons in some atoms or ions.

Complete the table. The first line is given as an example.

particle	number of protons	number of electrons	number of neutrons	symbol or formula
A	6	6	6
B	12	12	12
C	8
D	11	10	13

The table below gives information about particles.

Complete the table. The first line has been done for you.

Gallium is a Group III element.

Define the term element.

The following are gallium atoms.

Complete the following table.

atom	number of protons	number of neutrons	number of electrons

The table below gives the composition of six particles which are either atoms or ions.

Which particles are atoms? Explain your choice.

Which particle is a negative ion and why has this particle got a negative charge?

Which particles are positive ions?

Explain why particle A and particle D are isotopes.

Figure 1.1 shows the electronic configurations of five atoms, A, B, C, D and E.

Figure 1.1

Each letter may be used once, more than once or not at all.

Give the letter of the atom, A, B, C, D or E, that is in Group III of the Periodic Table.

Give the letter of the atom, A, B, C, D or E, that  has 13 protons.

Give the letter of the atom, A, B, C, D or E, that  is a noble gas. 

Give the letter of the atom, A, B, C, D or E, that forms a stable ion with a single negative charge.

Sulfuric acid is a compound.

Define the term compound.

Complete Table 2.1  to show the number of electrons, neutrons and protons in the sulfur atom and oxide ion.

Table 2.1 

	number of electrons	number of neutrons	number of protons
	16
		10

Complete Figure 2.2 to show the electronic configuration of a potassium ion.

This question is about elements X, Y and Z.

An atom of element X is represented as 

Name the different types of particles found in the nucleus of this atom of X.

What is the term for the total number of particles in the nucleus of an atom?

What is the total number of particles in the nucleus of an atom of ?

What is the electronic structure of the ion X^2–?

What term is used to describe atoms of the same element with different numbers of particles in the nucleus?

Separate: Chemistry and Extended Only

Part of the definition of relative atomic mass is ‘the average mass of naturally occurring atoms of an element’.

Some relative atomic masses are not whole numbers.

Element Y has only two different types of atom, ⁶⁹Y and ⁷¹Y

The ratio of atoms present in element Y is shown.

⁶⁹Y : ⁷¹Y = 3 : 2

• Calculate the relative atomic mass of element Y to one decimal place.

relative atomic mass: ..........

• Identify element Y.   
• element Y: ..........

Element Z is in Period 3 and Group V.

Explain in terms of electron transfer why Z behaves chemically as a non-metal.

Extended Only

Chlorine is in Group VII of the Periodic Table.

Two isotopes of chlorine are chlorine‑35 and chlorine‑37

State why these two isotopes of chlorine have the same chemical properties.

Chlorine is in Group VII of the Periodic Table.

Two isotopes of chlorine are chlorine‑35 and chlorine‑37.

Complete the table to show the number of electrons, neutrons and protons in each atom and ion.

	number of electrons	number of neutrons	number of protons

, and  are isotopes of sodium.

Describe how these sodium isotopes are the same and how they are different in terms of the total number of protons, neutrons and electrons in each.

same:

different:

, and   are isotopes of sodium.

Why do all three isotopes have an overall charge of zero?

The diagram shows part of the structures of five substances, A, B, C, D and E.

Answer the following questions about these structures.

Each structure may be used once, more than once or not at all.

Which two of these structures, A, B, C, D or E, are compounds?

Substance E is present in air.

Air is a mixture of different gases.

Describe two characteristics of a mixture.

Complete the table to show the number of electrons, protons and neutrons in the sulfur atom and zinc ion shown.

	number of electrons	number of neutrons	number of protons
			30

This question is about the structures of atoms and ions.

Define the term proton number.

Complete the table to show the number of protons, neutrons and electrons present in atoms of and .

	number of protons	number of neutrons	number of electrons

What term is used to describe atoms of the same element, such as and ?

Extended Only

Explain why the chemical properties of  and  are the same.

Complete the table to identify the atoms and ions which have the following numbers of protons, neutrons and electrons.

	number of protons	number of neutrons	number of electrons
	11	12	10
	4	5	4
	17	20	18

State the electronic structure of the following atom and ion.

Al:

S^2–: