Class 9 Practice Level 2 – Set 1 – Structure of the Atom

Total questions: 25

Which of the following pairs are isotopes of each other?

Topic: Isotopes

$ \displaystyle ^{{12}}C\text{ }an{{d}^{{14}}}N$

$ \displaystyle {^{{12}}C\text{ }an{{d}^{{13}}}C}$

$ \displaystyle {^{{14}}N\text{ }an{{d}^{{14}}}O}$

$ \displaystyle {^{{13}}C\text{ }an{{d}^{{14}}}N}$

None

How many electrons are in the third shell of an atom with atomic number 18?

Topic: Electron Configuration

None

In what year was the neutron discovered?

Topic: Discovery of Neutron

1897

1911

1932

1964

None

Which of the following is true about protons?

Topic: Atomic Structure

They are negatively charged.

They are found outside the nucleus.

They have a mass approximately equal to that of a neutron.

They have a mass much smaller than that of an electron.

None

Which of the following elements has no stable isotopes?

Topic: Isotopes

Hydrogen

Carbon

Uranium

Chlorine

None

How many electrons are in the valence shell of a chlorine atom (atomic number 17)?

Topic: Electron Configuration

None

The atomic number of an element is determined by the number of:

Topic: Atomic Number

Neutrons

Electrons

Protons

Nucleons

None

The Bohr model of the atom was proposed in which year?

Topic: Bohr’s Model

1897

1913

1932

1964

None

Which of the following particles is found in the nucleus of an atom?

Topic: Atomic Structure

Electron

Positron

Proton

Photon

None

10.

The atomic mass of an element is approximately equal to the total number of:

Topic: Atomic Mass

Electrons

Protons

Protons and neutrons

Neutrons

None

11.

Which subatomic particle has no charge?

Topic: Subatomic Particles

Proton

Electron

Neutron

Positron

None

12.

How many electrons can the second shell hold?

Topic: Electron Configuration

None

13.

In the Rutherford model of the atom, electrons are located:

Topic: Rutherford’s Experiment

In the nucleus

In fixed orbits around the nucleus

In a cloud around the nucleus

Randomly inside the nucleus

None

14.

Which subatomic particle was discovered first?

Topic: Atomic Structure

Electron

Proton

Neutron

Quark

None

15.

What is the atomic number of an element with 15 protons?

Topic: Atomic Number

None

16.

An element has 20 protons and 20 neutrons. What is its atomic mass?

Topic: Atomic Mass

20 amu

30 amu

40 amu

60 amu

None

17.

An atom has 10 electrons. How many electrons are in its outer shell?

Topic: Electron Configuration

None

18.

Who proposed the planetary model of the atom?

Topic: Atomic Models

Dalton

Thomson

Rutherford

Bohr

None

19.

The mass of a proton is approximately how many times that of an electron?

Topic: Atomic Mass

1948

1125

1530

1836

None

20.

If an element has 19 protons, what is its atomic number?

Topic: Atomic Number

None

21.

Which subatomic particle is found in the nucleus and has no charge?

Topic: Atomic Structure

Proton

Neutron

Electron

Positron

None

22.

How many electrons can the K-shell of an atom hold?

Topic: Electron Configuration

None

23.

Which of the following pairs represents isotopes of the same element?

Topic: Isotopes

$ \displaystyle ^{{14}}C\text{ }an{{d}^{{14}}}N$

$ \displaystyle ^{{12}}C\text{ }an{{d}^{{14}}}C$

$ \displaystyle ^{{12}}C\text{ }an{{d}^{{13}}}N$

$ \displaystyle ^{{13}}C\text{ }an{{d}^{{14}}}N$

None

24.

How many electrons are present in the outermost shell of a sulfur atom (atomic number 16)?

Topic: Electron Configuration

None

25.

In Rutherford's gold foil experiment, most alpha particles passed through the foil because:

Topic: Atomic Models

The foil was very thin

Atoms are mostly empty space

Alpha particles are very small

Alpha particles are very fast

None

1 out of 25

Time's up

Class 9 Practice Level 2 – Set 1 – Structure of the Atom

Welcome back