10-minute Quiz : Chapter 5 Atomic structure

Which of the following statements concerning potassium is/are correct?

(1) It is an element.

(2) The symbol of potassium is P.

(3) The following diagram can be used to represent the spatial arrangement of atoms in a piece of potassium under room conditions.

• A. (1) only
• B. (2) only
• C. (1) and (3) only
• D. (2) and (3) only

• A. one electron and two neutrons.
• B. one electron and two protons.
• C. one neutron and one proton.
• D. two neutrons and one proton.

An aluminium atom has 13 protons. The mass number of the aluminium atom is 27. How many neutrons are there in this aluminium atom?

• A. 13
• B. 14
• C. 27
• D. 40

The electron diagram of an atom of Z is shown below. Which of the following statements concerning Z are correct?

(1) The electronic arrangement of Z can be written as 2, 8, 8, 2.

(2) There are four occupied electron shells in an atom of Z.

(3) The atomic number of Z is 20.

• A. (1) and (2) only
• B. (1) and (3) only
• C. (2) and (3) only
• D. (1), (2) and (3)

Which of the following statements concerning an atom are correct?

(1) It is the smallest unit of an element which has the chemical properties of that element.

(2) It is made up of subatomic particles.

(3) It is electrically neutral.

• A. (1) and (2) only
• B. (1) and (3) only
• C. (2) and (3) only
• D. (1), (2) and (3)

The relative atomic mass of an element is defined as

• A. the mass of an atom of the element relative to the mass of a carbon-12 atom.
• B. the mass of an atom of the element relative to the mass of a hydrogen-1 atom.
• C. the average of the relative isotopic masses of all of its naturally occurring isotopes on the ¹²C = 12.00 scale.
• D. the weighted average of the relative isotopic masses of all of its naturally occurring isotopes on the ¹²C = 12.00 scale.

• A
• B
• C
• D

• A. They have the same atomic number.
• B. They have the same mass number.
• C. They have the same melting point.
• D. They have the same density.

Nitrogen has two naturally occurring isotopes, ¹⁴N and ¹⁵N, with relative abundances of 99.63% and 0.37% respectively. What is the relative atomic mass of nitrogen (correct to three decimal places)?

• A. 14.000
• B. 14.004
• C. 14.500
• D. 14.996

Which of the following statements concerning a neutron are correct?

(1) It has no electric charge.

(2) It can be found in the nucleus of an atom.

(3) It weighs much less than a proton.

• A. (1) and (2) only
• B. (1) and (3) only
• C. (2) and (3) only
• D. (1), (2) and (3)