Year : 
2008
Title : 
Chemistry
Exam : 
WASSCE/WAEC MAY/JUNE

Paper 1 | Objectives

1 - 10 of 44 Questions

# Question Ans
1.

The mass spectrometer can be used to measure mass of

A. an atom

B. an electron

C. a proton

D. a neutron

A

2.

Find the number of neutrons in an atom represented by 4521X.

A. 21

B. 24

C. 45

D. 66

B

3.

The valence electrons in a chloride ion are [17CI]

A. 2p electrons only

B. 3s and 3p electrons only

C. 3p and 3d electrons only

D. 3p electrons only

B

4.

What is the atomic number of an element whose cation Y+ has the electronic configuration 1s22s22p6?

A. 9

B. 10

C. 11

D. 12

C

5.

Atom \(^{234} _{88} Q\) decay by alpha emission to give an atom R. The atomic number and mass number of atom R are respectively

A. 86 and 230

B. 87 and 234

C. 88 and 233

D. 90 and 238

Detailed Solution

\(^{234} _{88} Q \to R + ^4 _2 He\)
\(\therefore R = ^{234 - 4} _{88 - 2} R\)
= \(^{230} _{86} R\)
6.

Which of the following statements is not true of halogens?

A. they exist in different physical states

B. they exist as diatomic molecules

C. their ionic radii decrease down the group

D. their melting and bolling points increase down the group

C

7.

Elements in the same group of the periodic table have

A. the same number of valence electrons

B. the same number of electron shells

C. different chemical behaviour

D. the same atomic size

A

8.

Consider the following elements and their electronic configurations
W: 1s22s2
X: 1s 22s22p6
Y: 1s22s22p63s2
Z: 1s22s22p63s23p2. Which of t

A. W and X only

B. Y and Z only

C. W and Y only

D. W, Y and Z only

C

9.

Arrange the following elements in order of increasing electron affinity: Br2CI2
I 2
F 2

A. I 2CI2Br2F 2

B. I 2Br2CI2F 2

C. CI2 I 2Br2F 2

D. Br2CI2 I 2 F 2

B

10.

Water molecules are held together by

A. covalent bond

B. hydrogen bond

C. ionic forces

D. van der Waals forces

B

1.

The mass spectrometer can be used to measure mass of

A. an atom

B. an electron

C. a proton

D. a neutron

A

2.

Find the number of neutrons in an atom represented by 4521X.

A. 21

B. 24

C. 45

D. 66

B

3.

The valence electrons in a chloride ion are [17CI]

A. 2p electrons only

B. 3s and 3p electrons only

C. 3p and 3d electrons only

D. 3p electrons only

B

4.

What is the atomic number of an element whose cation Y+ has the electronic configuration 1s22s22p6?

A. 9

B. 10

C. 11

D. 12

C

5.

Atom \(^{234} _{88} Q\) decay by alpha emission to give an atom R. The atomic number and mass number of atom R are respectively

A. 86 and 230

B. 87 and 234

C. 88 and 233

D. 90 and 238

Detailed Solution

\(^{234} _{88} Q \to R + ^4 _2 He\)
\(\therefore R = ^{234 - 4} _{88 - 2} R\)
= \(^{230} _{86} R\)
6.

Which of the following statements is not true of halogens?

A. they exist in different physical states

B. they exist as diatomic molecules

C. their ionic radii decrease down the group

D. their melting and bolling points increase down the group

C

7.

Elements in the same group of the periodic table have

A. the same number of valence electrons

B. the same number of electron shells

C. different chemical behaviour

D. the same atomic size

A

8.

Consider the following elements and their electronic configurations
W: 1s22s2
X: 1s 22s22p6
Y: 1s22s22p63s2
Z: 1s22s22p63s23p2. Which of t

A. W and X only

B. Y and Z only

C. W and Y only

D. W, Y and Z only

C

9.

Arrange the following elements in order of increasing electron affinity: Br2CI2
I 2
F 2

A. I 2CI2Br2F 2

B. I 2Br2CI2F 2

C. CI2 I 2Br2F 2

D. Br2CI2 I 2 F 2

B

10.

Water molecules are held together by

A. covalent bond

B. hydrogen bond

C. ionic forces

D. van der Waals forces

B