Atomic Structure Quiz A level

What is the relative mass of a neutron?

• 1/1800

• 0

• 1

• -1

What is the relative charge of an electron?

• +1

• 0

• 1/1800

• -1

How is the number of neutrons in an atom calculated?

• A + Z

• A - Z

• Z - A

• Z / A

What does the atomic number (Z) represent?

• The total number of protons and neutrons in the atom

• The number of neutrons in the nucleus

• The number of protons in the nucleus

• The mass number of the atom

What is the relative isotopic mass?

• The average mass of a molecule compared to one twelfth of the mass of one atom of carbon-12

• The mass of one isotope compared to one twelfth of the mass of one atom of carbon-12

• The weighted mean mass of one atom compared to one twelfth of the mass of one atom of carbon-12

• The sum of the masses of the protons and neutrons in the atom

Which formula represents the calculation of the Relative Atomic Mass (R.A.M) of an element?

• R.A.M = Σ (isotopic mass × abundance) / 100

• R.A.M = Σ (isotopic mass × percentage abundance) / total relative abundance

• R.A.M = Σ (isotopic mass × relative abundance)

• R.A.M = (isotopic mass × percentage abundance) / 100

What is the relative atomic mass (R.A.M) of tellurium given the following abundance data: 124-Te relative abundance 2, 126-Te relative abundance 4, 128-Te relative abundance 7, 130-Te relative abundance 6?

• 127.8

• 128.2

• 126.4

• 129.1

If the relative atomic mass of copper is 63.5 and copper has two isotopes 63-Cu and 65-Cu, what is the percentage abundance of 63-Cu?

• 72.5%

• 27.5%

• 50%

• 63.5%

Why does the 160 peak in the mass spectrum for Br have double the abundance of the other two peaks?

• Because Br has a higher atomic mass than Cl.

• Because there is double the probability of 160 Br-79-Br-81 as can be Br-79-Br-81 and Br-81-Br-79.

• Because Br-81 is more abundant than Br-79.

• Because the mass spectrometer is more sensitive to Br-81.

What is the relative abundance of the Cl-35 isotope?

• 75%

• 25%

• 50%

• 100%