notes

Question 1

what is the definition of relative atomic mass?

Answer 1

weighted average mass of 1 atom of an element compared to 1/12 mass of 1 atom of carbon-12

Question 2

how does mass spectrometry produce positive ions?

Answer 2

atoms are bombarded by high energy e-

Question 3

what 3 types of positive ions does mass spectrometry produce?

Answer 3

• positively charged atoms
• positively charged molecules
• positively charged fragments of molecules

Question 4

how do the products of mass spectrometry provide information on relative mass and abundance?

Answer 4

each isotope produces a m/z ratio and abundance

Question 5

what is a quantum shell?

Answer 5

defines the energy level of an electron

Question 6

what is an orbital?

Answer 6

region within an atom with high probability of finding an e-
that could hold up to 2 e- with opposite spins

Question 7

what is the electronic configuration?

Answer 7

number of electrons in each sublevel in each energy level of the atom

Question 8

what are the 2 exceptions to Hund’s rule? name their electronic arrangement.

Answer 8

Cu: [Ar]18 4s1 3d10
Cr: [Ar]18 4s1 3d5

Question 9

define first ionisation energy.

Answer 9

energy required to remove an e- from 1 mole of gaseous atom

Question 10

define periodicity.

Answer 10

regularly repeating pattern of atomic, physical & chemical properties with increasing atomic number

Question 11

what is the trend in atomic radii across a period? explain why.

Answer 11

atomic radii decreases with increasing atomic number - more positive charge attraction for e- in the same shell with similar shielding

Question 12

what does transition elements form stable ions with?

Answer 12

forms ion with incomplete d sub-shell

Question 13

what is the definition of relative isotopic mass?

Answer 13

mass of an atom of that isotope compared to 1/12th mass of a C-12 atom