chapter 2 - atoms, ions and compounds

Question 1

relative atomic mass, Ar

Answer 1

weighted mean mass of an atom of an element compared to 1/12th of the mass of C (it is “weighted” because of the presence of isotopes)

Question 2

calculation for relative atomic mass

Answer 2

(mass1 x abundance1) + (mass2 x abundance2) / 100

Question 3

relative molecular mass, Mr

Answer 3

the weighted mean mass of a molecule compared with 1/12th of the mass of C

Question 4

formula for nitrate ions

Answer 4

NO3-

Question 5

formula for carbonate ions

Answer 5

CO32-

Question 6

formula for sulfate ions

Answer 6

SO42-

Question 7

formula for hydroxide ions

Answer 7

OH-

Question 8

formula for ammonium

Answer 8

NH4+

Question 9

formula for zinc

Answer 9

Zn2+

Question 10

formula for silver ions

Answer 10

Ag+

Question 11

formula for nitrite ions

Answer 11

NO2-

Question 12

formula for hydrogencarbonate ions

Answer 12

HCO3-

Question 13

formula for manganate ions

Answer 13

MnO4-

Question 14

formula for sulfite ions

Answer 14

SO32-

Question 15

formula for dichromate ions

Answer 15

Cr2O72-

Question 16

formula for phosphate ions

Answer 16

PO43-

Question 17

weighted mean mass

Answer 17

takes into account the relative abundancies of isotopes

Question 18

low volatility

Answer 18

a molecule that doesn’t evaporate into a gas easily