atoms, ions and compounds

Question 1

what are the diatomic molecules?

Answer 1

nitrogen, oxygen, fluorine, bromine, chlorine, iodine, astatine

Question 2

what are the D Block charges?

Answer 2

Pb2+
Ag+
Zn2+
Cu2+ or Cu+
Fe3+ or Fe2+

Question 3

what are the molecular ions?

Answer 3

Ammonium NH4 +
Hydroxide OH -
Nitrate NO3 -
Hydrogen Carbonate HCO3 -
Sulfate SO4 2-
Carbonate CO3 2-
Phosphate PO4 3-

Question 4

what is the official definition of relative formula mass?

Answer 4

the weighted mean/average mass of the formula unit, compared to 1/12th the mass of an atom of carbon 12

Question 5

what is relative formula mass?

Answer 5

the same as relative molecular mass, but used when dealing with giant structures/ionic and metallic compounds

Question 6

what is the official definition of relative atomic mass?

Answer 6

the weighted mean/average mass of an atom of an element compared to 1/12th the mass of an atom of carbon 12

Question 7

how do you calculate relative atomic mass?

Answer 7

Ar = ((mass1 x abundance1) + (mass2 x abundance2)…) /100

Question 8

how do you calculate relative atomic mass if the abundance is a ratio? (quicker way)

Answer 8

divide by the sum of the parts rather than 100 (and substitute each abundance for each respective part)

Question 9

what is the official definition of relative isotopic mass?

Answer 9

the mass of an atom/isotope compared 1/12th of the mass of an atom of carbon 12

Question 10

what is relative isotopic mass?

Answer 10

the mass of a singular isotope (not an average). therefore, it will always be a whole number.

Question 11

how do you calculate relative isotopic mass?

Answer 11

protons + neutrons (the mass number of the isotope).

Question 12

what is relative molecular mass?

Answer 12

the mass of a molecule (multiple atoms joined e.g. CH4)

Question 13

what is the official definition of relative molecular mass?

Answer 13

the weighted mean/average mass of a molecule compared to 1/12th the mass of an atom of carbon 12.

Question 14

how do you calculate relative molecular mass?

Answer 14

add the mass numbers of the individual atoms in the molecule together (e.g CH4 = 12 + (1 x 4) = 16)

Question 15

what is a cation?

Answer 15

a positive ion

Question 16

what is an anion?

Answer 16

a negative ion

Question 17

what are the rules for constructing ionic equations?

Answer 17

1. write the full balanced equation
2. for aqueous ionic substances, write the ions separately (e.g. NaCl = Na+ + Cl-)
3. leave the formula for solids, liquids and gases in full (eg. NH3)
4. cancel all spectator ions (those which stay the same charge)

Question 18

what is the formulae of the acids?

Answer 18

hydrochloric acid HCl
sulfuric acid H2SO4
nitric acid HNO3
phosphoric acid H3PO4

Question 19

how do you interpret a mass spectrometer graph?

Answer 19

the y-axis shows the percentage abundances of different isotopes, and the x-axis shows these isotopes by mass number.

Question 20

what happens in a mass spectrometer?

Answer 20

1. a sample is placed in the mass spectrometer
2. the sample is vaporised and then ionised to form positive ions
3. the ions are then accelerated into a deflector (heavier ions = slower)
4. heavier ions are more difficult to deflect than lighter ions so hit the mass spectrometer at different points