1. Consider the following statements about fossil fuels and biofuels.
I. Production of biofuels does not damage the environment.
II. Combustion of both biofuels and fossil fuels generates greenhouse gases.
III. Biofuels and fossil fuels are both renewable as they are produced from plants.
Which of the statements above are correct?
A. I only
B. II only
C. I and II only
D. I and III only

Solution

2. Consider the following statements about coal seam gas and petroleum gas.
I. Coal seam gas and petroleum gas are both mixtures.
II. Coal seam gas and petroleum gas both combust to produce carbon dioxide.
III. Coal seam gas and petroleum gas are both fossil fuels.
Which of the above statements are correct?
A. I and II only
B. I and III only
C. II and III only
D. I, II and III

Solution

A student investigated the viscosity of several biofuels.
The flow rate of each biofuel through a narrow glass tube was measured. The results are presented in the tables below.

Table 1: Flow rate (mL /min) of biodiesels produced using sodium hydroxide, NaOH(aq), catalyst

Table 2: Flow rate (mL /min) of biodiesels produced using potassium hydroxide, KOH(aq), catalyst

3. How many independent variables are there in this investigation?
A. 1
B. 3
C. 4
D. 6

4. Select the most valid conclusion that can be drawn from the student’s results presented in Table 1 and Table 2.

A. Biodiesels made from sunflower oil have a higher viscosity than biodiesels made from canola oil.
B. Biodiesels made from methanol have a lower viscosity than biodiesels made from ethanol.
C. Biodiesels are unsuitable for use in cold climates because they have a higher viscosity than petrodiesels.
D. Biodiesels made using NaOH(aq) catalyst have a lower viscosity than biodiesels made using KOH(aq) catalyst.

Solution