The 2 most common desalination techniques as distillations and reverse osmosis. Both of them require energy to remove salts from sea water or brackish water and thus inherently are expensive. if a less expensive option is available, such as hauling fresh water from a distance, then this option is used.

Water is a polar solvent and prefer water-soluble compounds to dissolve such as vitamins, being able to form hydrogen bonding between the solvent and the solute. While on the other hand, fat-soluble compounds may not be need to be water-soluble or polar compounds. Fat-soluble compounds may be non-polar compounds that dissolve in fat-soluble or non-polar solvents.

(a) To reduce usage of clothes dryers to save electricity. Less fuels burnt at power plants, hence less NO(x) and SO(x) emission, reducing acid rain.

(b) Reducing usage of private cars can reduce automobile emission which contain NO(x) mainly, hence reducing acid rain.

(c) Running with small loads are less efficient and waste electricity, hence this causes more fuel burnt, causing more acid rain formation.

(d) This allow more efficient heat transfer and require less electricity to heat up the water, saving electricity and reducing emission.

(e) To save on fuels needed to transport the produce overseas, reducing emissions in power plants.

(a) Coal-fired plants produce anthrogenic microscopic particulate matter that produce haze that results in poor visibility in air.

(b) Assuming the pH of natural rain is 5.6, then the pH of the rainfall in the park is 4.6

(a) Exothermic because it gives off heat to the environment
(b) Endothermic because water absorb heat from the skin to get evaporated
(c) Endothermic because ice absorbs heat to melt into liquid state

The bond strength in the product is significantly greater than that of the reactant. This is because for exothermic reaction to occur, ΔH=|Energy of reactants|-|Energy of products|<0
It is also known that energy is released when bonds are formed in the product and energy is needed to break the bond in the reactant side.

Heat is a consequence of motion at the molecular level while temperature is a measure of average of that motion.
Set up an experiment with a cup of hot and cold water respectively. Place one hand on the hot cup from until no heat can be felt. Then, place the other hand on the cold cup to feel the ‘coldness’. This feeling of coldness is due to the flow of heat from the ‘hot’hand to the cold cup.

(a) Knocking characteristic of 98% isoctane and 2% heptane
(b) Fuel does contain oxygenates as oxygenates increases the octane rating of the premium gasoline.

Process (a) is exothermic because it gives off net heat to the environment as it burns.
Process (B0 is endothermic because water absorbs heat from the skin to overcome its intermolecular bonds which are van der waals forces and hydrogen bondings between the molecules in order to get evaporated into gas molecules.
Process (c) is endothermic because ice absorbs heat from the environment to melt into liquid state.

The bond strength in the product should be significantly greater than that in reactant. This is because for exothermic reaction to occur, the delta enthalpy = |energy of reactant| – |energy of product| < 0. It has been already known that energy is released when bonds are formed to form the product while energy is required to break the bond in the reactant side.

Temperature is a measure of average of the motion of the molecules while heat is the consequence of motion at molecular level.

Set an experiment with 1 hot and 1 cold cup of water separated away from other. Place one hand on the hot cup until no heat can be felt. Then, place the same hand on the cold cup to feel the “coldness”. This feeling of “coldness” is due to the flow of heat from the hot hand to the cold cup of water.

Knocking characteristics of this gasoline is 98% iso-octane and 2% heptane.

We can’t tell whether the fuel does contain oxygenates because octane rating alone does not indicate whether oxygenates are added in.