1. Determine the number of electrons, protons and neutrons in each isotope of titanium based on the table below. Determine its atomic mass.

Isotope

Mass (Da)

Natural Abundance (%)

Electrons

Protons

Neutrons

Atomic Mass

⁴⁶Ti

45.9526294

8.25

⁴⁷Ti

46.9517640

7.44

⁴⁸Ti

47.9479473

73.72

⁴⁹Ti

48.9478711

5.41

⁵⁰Ti

49.9447921

5.18

2. For each compound listed below write down the correct formula and calculate the formula mass.

• Iron(III) sulfide
• Aluminum nitrate
• Carbon tetrachloride
• Perchloric acid
• Ammonium hydroxide

3. Aluminum is refined from the mineral bauxite, which is mostly aluminum hydroxide (Al(OH)3). Presuming that an ore sample is approximately 54% bauxite, how much Al could be extracted from 1 kg of ore?

4. Calcium carbonate (a weak base) reacts with nitric acid (a strong acid) quantitatively in the following reaction to form calcium nitrate, water and carbon dioxide:

How many kg of carbon dioxide (CO₂) are formed per kg of CaCO₃ reacted? Presume that there is an excess of HNO₃ available.

5. Metallic sodium reacts vigorously with liquid bromine in the following reaction:

1 kg of Na is brought into contact with 3 kg of liquid bromine. Presuming that the reaction is quantitative and proceeds to completion, determine the limiting reagent and the quantity of NaBr formed. Determine the amount of excess reagent remaining after the reaction is complete.

6. The combustion of gasoline (C₈H₁₈) with excess oxygen produces carbon dioxide and water.

• W rite a balanced chemical reaction for the combustion of gasoline to yield carbon dioxide and water.
• Presuming that a tank of gasoline contains 80 liters and that its density is 0.77 kg/liter, determine how many kg of CO₂are produced for each tank of gasoline burned.