Chp 1

Question 1

How do we test for carbon dioxide?
CO2

1B

Answer 1

• CO2 bubbled thru calcium hydroxide solution (limewater)
• White percipitate of calcium carbonate forms
• Limewater goes cloudy / milky
• Ca(OH) 2 (aq) + CO2 (g) —> CaCO3 (s) + H2O (l)

Question 1

How do we test for sulfate ions?

1B

Answer 1

• Presence of sulfate ions can be shown by the addition of barium ions
• White percipitate forms —> Barium Sulfate

Question 2

How do we test for halide ions?

1B

Answer 2

• Presence of halide ions in solution shown by addition of silver ions
• Forms silver nitrate solution
• Percipitate that forms are silver halides

Question 3

How do we define Relative Atomic Mass?

1C

Answer 3

• The weighted mean (average) mass of an atom compared to 1/12 of mass of an atom of 12C

Question 4

How do we describe mole?

1C

Answer 4

• Amount of a substance that contains the same number of particles as the number of carbon atoms in exactly 12g of the 12C isotope

Question 5

What are the relative masses of P,N,E

Answer 5

Proton > 1
Neutron > 1
Electron > 1/1840