One of the processes involved in desalination is distillation. Distillation is not a good technique to produce potable drinking water because distillation technique removes salts completely thus creating pure water. Drinking water that we use usually contains mineral, so it is not really a good process for drinking usage. Distillation is also very costly and requires large amount of energy and resources.

If it is water-soluble, it is a polar compound because polar solute dissolves in polar solvent. Fat-soluble compounds is non-polar and dissolves in non-polar solvents.

For a, b, c& d, it concerns the methodologies on reducing electricity consumption. With lesser electricity consumed, power plants would burn lesser fuel to spin the turbine for electricity. Lesser fuel burnt means lesser emissions of nitrogen oxides and sulfur oxides which are key sources of acid rain production.

For e, it takes a large amount of energy for fuel to travel from “field to plate” if food were imported. Buying locally grown produce and produced food reduces the amount of energy consumed on transportation and means less burning of fossil fuels where its by-products would lead to acid rain.

a. Coal-fired plants produce lots of sulfur oxides and nitrogen oxides and also produce smoke and particulate matter which causes haze.

b. pH would be about 5 because natural rain has an estimated pH of 6

A. Exothermic. Heat is released when charcoal briquette burns.
B. Endothermic. Heat is absorbed for water to evaporate and hydrogen bonding between water molecules are broken.
C. Endothermic. Heat is absorbed and required to reach the melting point of ice.

Heat is released from forming bonds and heat is absorbed to break bonds. For an exothermic reaction, heat is released. Therefore, heat released during bond formation (products) is greater that the heat absorbed for bond breaking (reactants). Hence the product would have a greater bond strength than the reactants and the products are more stable.

Heat is the energy that flows from the hotter object to the colder object, it is the consequence of motion at the molecular level whereas temperature is a measure of the average speed of that motion.

A practical example would be a hot cup of coffee cooling down. As it cools gradually, heat from the coffee is transferred to the surrounding air which is at a lower temperature. The rate at which heat transfers is the temperature. Temperature difference causes heat to flow from the hotter region to cooler region.

A. Octane rating of 98 means a knocking characteristic of 98% isooctane and 2% heptane.

B. Octane rating measures the ability of gasoline to burn smoothly without knocking. Fuels that contain oxygenates generally have a higher octane rating. The higher the octane rating, the higher possibility that it contains oxygenates. Octane rating does not tell us whether oxygenates are present or not but only the likelihood.