2.1.1 - Atomic structure and isotopes

Question 1

Explain what is meant by the term relative atomic mass of an element. (2)

Answer 1

• (Weighted) mean/average mass of an atom
• Compared with 1/12th mass of carbon-12 / compared with mass of carbon-12 which is 12

Question 2

State two differences between isotopes of the same element. (1)

Answer 2

• Different numbers of neutrons
• Different (atomic) masses/mass numbers
• Different physical properties

Question 3

State the similarities and differences between the atomic structure of isotopes of the same element. (2)

Answer 3

• (Same) number of protons and electrons
• (Different) number of neutrons

Question 4

Define the term relative atomic mass. (3)

Answer 4

• The (weighted) mean mass of an atom (of an element)
• Compared with 1/12th (the mass)
• Of (one atom of) carbon-12

Question 5

What is meant by the term isotopes? (1)

Answer 5

• Atom(s) of an element with different numbers of neutrons (and with different masses)

Question 6

Explain why different isotopes can have the same chemical properties. (1)

Answer 6

• Same number of electrons in outer shell
  or
• Same electron configuration/electron structure

Question 7

Define the term relative isotopic mass. (3)

Answer 7

• The mass of an atom of an isotope
• Compared with 1/12th (the mass)
• Of (one atom of) carbon-12