THE STRUCTURE OF THE ATOM

2.2.1 Describe the development of atomic model

1. State the findings(theory) and draw the atomic model of each named scientists below on the development of atomic model

Name of scientist Theory Atomic Model

John Dalton(1766 – 1844)

J.J. Thomson(1856 – 1940)

Ernest Rutherford(1871 – 1937)

Neils Bohr(1885 – 1962)

James Chadwick(1891 – 1974)

2.2.2 State the main subatomic particles of an atom

1. An atom is made up of 3 subatomic particles. The subatomic particles that are present in an atom are

(a) ___________________________

(b) ___________________________

(c) ___________________________

2. The symbol for an atom of aluminium is written as .

State the number of subatomic particles that are present in aluminium atom. Proton: __________, Neutron : __________ and Electron : ___________

2.2.3 Compare and contrast the relative mass and the relative charge of the protons, electrons and neutrons.

1. Complete the table below to compare and contrast the relative mass and relative charge of the protons, electrons and neutrons

Subatomic particle

Relative atomic mass

Relative charge Position

Proton,p In the nucleus

Neutron,n In the nucleus

Electron,e- Orbiting in shells outside the nucleus

2.2.4 Define proton number

1. The proton number of an element is the ____________________ in its atom.

2.2.5 Define nucleon number 1. = +

2.2.6 Determine the proton number

1. Bromine – 80 has 45 neutrons. Its proton number is _______________.

2. An atom Argon has 18 electrons and 20 neutrons. Its proton number is _________.

3. Atom X has 4 protons and 5 neutrons. The proton number of element X is _______.

Nucleon number

2.2.7 Determine the nucleon number

1. Atom X has 4 protons and 5 neutrons. Find the nucleon number of X.

2.2.8 Relate the proton number to the nucleon number.

1. The proton number of helium is 2. What is the possible nucleon number of helium?

2. Given the proton number of X is 6. What is the possible nucleon number of X?

2.2.10 Write the symbol of elements.

1. A fluorine atom has 9 protons and 10 neutrons. What is the proton number and nucleon number of the atom? Represent the atom in the form of A

ZX.

2. Bromine-80 has 45 neutrons. What are the proton number and nucleon number of the atom? Represent the atom in the form of A

ZX.

2.2.11 Determine the number of neutrons, protons and electrons from the proton number and the nucleon number and vice versa.

1. Which of the following elements has the most neutrons in its atom ?32

16S , 3919K , 35

17Cl , 4018Ar

2. Atom X has 4 protons and 5 neutrons. Find the proton and nucleon number of element X.

3. Given the proton number of carbon-14 is 6. How many protons and neutrons does it has?

2.2.12 Construct the atomic structure.

1. An atom of element Y has 17 protons and 20 neutrons in its nucleus. Write the electron arrangement of atom Y.

2. Given the number of protons of Z is 19. Draw a diagram to show the arrangement of electrons around the nucleus of atom Z.

Answer:

2.2.1 Question 1Name of scientist

Theory Atomic Model

John Dalton(1766 – 1844)

Proposed that:(a) all elements are made up of small indivisible particles called atoms(b) the atoms of one element are alike, but differ from atoms of other elements.

J.J. Thomson(1856 – 1940) Suggested that the atom is

appositively charged sphere with electrons embedded in it.

Ernest Rutherford(1871 – 1937)

Discovered the protons and suggested that the protons are concentrated in the center of the atom which is called nucleus. The nucleus is surrounded by a cloud of electrons.

Neils Bohr(1885 – 1962) Proposed that the electrons are

arranged in orbits surrounding the nucleus.

James Chadwick(1891 – 1974) Discovered the neutrons. Proposed

that the nucleus contains protons and neutrons with electron moving in orbits surrounding the nucleus.

2.2.2 Question 1

(a) proton (b) electron (c) neutron

Question 2

Nucleus that contain protons

Nucleus that contain protons andneutrons

Nucleus that contains protonsElectron moves outside the nucleus

Proton = 13 ; neutron = 14 ; electron = 13

2.2.3 Question 1

Subatomic particle

Relative atomic mass

Relative charge

Position

Proton,p 1 +1 In the nucleus

Neutron,n 1 0 In the nucleus

Electron,e- -1 Orbiting in shells outside the nucleus

2.2.4 Question 1

Number of proton

2.2.5 Question 1 Proton number + neutron number

2.2.6 Question

1. 352. 183. 4

2.2.7 Question 1 9

2.2.8 Question 14

Question 212, 13, 14

2.2.10 Question 19, 19 19

9X

Question 235, 80, 80

35X

2.2.11 Question 1Ar

Question 24, 9

Question 3

6,8

2.2.12 Question 12.8.7

Question 22.8.8.1