Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
Atomic Structure
108 practice questions
Topics covered
Practice questions
31–40 of 108
Question 31
3 marks · Normal
Answer and see the solution →An atom of magnesium has atomic number 12 and mass number 25.
Calculate the number of neutrons in this atom. Show your working.
Question 32
3 marks · Normal
Answer and see the solution →Explain the difference between the atomic number and the mass number of an atom. Give an example of each.
Question 33
4 marks · Normal
Answer and see the solution →The table below shows information about three atoms.
Properties of three atoms Atom Atomic number Mass number A 6 14 B 8 16 C 11 23 (a)[2 marks]For atom A, state the number of protons, neutrons and electrons (assuming atom A is neutral).
(b)[2 marks]Which atom in the table has the greatest number of neutrons? Show your reasoning.
Question 34
1 mark · Normal
Answer and check →Which statement about isotopes is correct?
- A.Isotopes have different numbers of protons but the same number of neutrons.
- B.Isotopes have the same number of protons but different numbers of neutrons.
- C.Isotopes have different atomic numbers but the same mass number.
- D.Isotopes have different numbers of electrons only.
Question 35
2 marks · Normal
Answer and see the solution →Name the three types of sub-atomic particles in an atom and state where each is located.
Question 36
4 marks · Normal
Answer and see the solution →An atom of lithium has atomic number 3 and mass number 7.
(a)[1 mark]State what the atomic number tells you about the atom.
(b)[2 marks]Explain how to calculate the number of neutrons in this atom and give the answer.
(c)[1 mark]Lithium has isotopes. Define 'isotope'.
Question 37
2 marks · Hard
Answer and see the solution →Helium-3 is an isotope of helium with a mass number of 3. It has 2 protons. State the number of neutrons and electrons in a neutral atom of helium-3.
Question 38
5 marks · Hard
Answer and see the solution →The element chlorine occurs naturally as two main isotopes: chlorine-35 and chlorine-37. The relative abundances of these isotopes are 75% chlorine-35 and 25% chlorine-37.
(a)[1 mark]Define the term 'isotope'.
(b)[1 mark]State the atomic number of chlorine.
(c)[1 mark]Explain, using your knowledge of atomic structure, why chlorine-35 and chlorine-37 are isotopes of the same element.
(d)[2 marks]Calculate the relative atomic mass of chlorine to 1 decimal place. Show your working.
Question 39
2 marks · Hard
Answer and see the solution →State the relative mass and relative charge of a neutron, and explain how these properties compare to those of a proton.
Question 40
1 mark · Easy
Answer and see the solution →Naturally occurring boron is made up of two isotopes: 20% of its atoms have a mass number of 10, and the rest have a mass number of 11. What is the relative atomic mass of boron to the nearest whole number?