Atoms and Molecules | Live Education Quiz

1

Who proposed the atomic theory?

A John Dalton B J.J. Thomson C Ernest Rutherford D Niels Bohr

2

Which subatomic particle has no charge (neutral)?

A Proton B Neutron C Electron D Positron

3

What is the nucleus of an atom?

A The outer region containing electrons B The dense central core containing protons and neutrons C A shell of electrons D A collection of molecules

4

What is the atomic number of an atom?

A The total number of protons B The total number of neutrons C The total number of electrons D The total mass of the atom

5

What is the charge of a neutron?

A Positive B Negative C Neutral D Both positive and negative

6

What is the atomic number of oxygen?

A 8 B 16 C 6 D 10

7

What is the valency of an element?

A The number of electrons in the outermost shell B The combining capacity of an atom C The total number of protons D The number of neutrons

8

What is the chemical formula of water?

A H2O B CO2 C NaCl D CH4

9

What is the difference between an atom and a molecule?

A An atom is the smallest unit of an element; a molecule is made of two or more atoms B An atom is larger than a molecule C A molecule is the smallest unit of an element D There is no difference

10

What is an ionic bond?

A A bond formed by sharing electrons B A bond formed by transferring electrons C A bond between non-metals D A bond between molecules

11

What is the electron shell?

A A region around the nucleus where electrons are likely to be found B The nucleus of an atom C The part of an atom containing protons D A neutral particle

12

What is the law of constant proportions?

A Elements combine in fixed ratios by mass B Elements combine in variable ratios C Compounds can be separated easily D Atoms are indivisible

13

What is the chemical formula of sodium chloride?

A H2O B CO2 C NaCl D CH4

14

How many electrons are in a neutral atom of hydrogen?

A 0 B 1 C 2 D 3

15

What is a cation?

A A positively charged ion B A negatively charged ion C A neutral ion D A molecule

16

How many protons are in a neutral atom of oxygen (atomic number 8)?

A 6 B 8 C 16 D 10

17

What is the law of conservation of mass?

A Matter can be created or destroyed B Matter cannot be created or destroyed C Mass is lost during reactions D Mass is gained during reactions

18

What is the chemical formula of carbon dioxide?

A H2O B CO2 C NaCl D CH4

19

What is the valency of hydrogen?

A 1 B 2 C 3 D 4

20

What is a compound?

A A pure substance made of two or more elements chemically combined B A mixture of different substances C An element D A homogeneous mixture

21

What is the mass number of an atom with 6 protons and 6 neutrons?

A 6 B 12 C 18 D 24

22

What is an ion?

A A neutral atom B A charged atom or molecule C A molecule with no charge D A type of element

23

Which of the following is a covalent compound?

A NaCl B KCl C H2O D MgO

24

What is the mass number of an atom?

A The total number of protons B The total number of neutrons C The total number of protons and neutrons D The total number of electrons and protons

25

Which of the following is a diatomic molecule?

A H2 B H2O C NaCl D CO2