OCR GCE Chemistry 2.1.1c-e Atoms & Isotopes

COMPLETE THE DEFINITION (using '1/12th')

"relative isotopic mass is the mass of an atom...

Answer explanation

know the exact wording from the spec (2.1.1c)

COMPLETE THE DEFINITION (using '1/12th')

"relative atomic mass is the...

Answer explanation

know the exact working from the spec (2.1.1c)

TICK ALL TRUE statements about mass spectrometry

• the units on the x-axis are: g mol^–1

• the y axis is always: % abundance

• the tallest peak represents the heaviest isotope

• the number of peaks is the number of isotopes of the element being analysed

Answer explanation

2.1.1(d)

Answer explanation

check the spec: 2.1.1d(ii)

What can be calculated using this formula?
 $\frac{\Sigma\left(RIM\times rel.\ abd.\right)}{\Sigma\left(rel.\ abd.\right)}=\ ?$ 

Answer explanation

check the spec: 2.1.1d(ii)

M_r(Cl₂) = ?

no units needed

Answer explanation

remember that M_r and A_r must be to 1dp unless stated otherwise

M_r(SO₃) = ?

no units needed

which other term can be used to describe

the molar mass of SO₄^2–

How many isotopes does this element seem to have?

The spectrum shows isotopes of an element.

How many neutrons+protons are in the LEAST abundant isotope of this element,