a. C6(H2O)6= C6H12O6
c. glucose, an isomer of fructose, is less sweet than the latter. Isomers have different chemical properties

chemical refers to chemical compounds, and all types of foods have chemical compounds

Organic food is defined as lacking synthetic pesticides (chemical) used on crops. It is impossible to go on an organic/chemical free diet because an item can be labelled organic when only 95% of its ingredients are organically grown. Hence, some chemicals would no doubt slip through. Some ingredients are very difficult to be sourced organically, thus they are exempted from the requirements, and again, these ingredients may contain certain chemicals that people would wish to avoid. Organic pesticieds are used in place of synthetic pesticides when growing organic food. However, there are no real differences between organic and synthetic pesticides. Organic pesticides come from natural sources, but because they were never processed, they can contain the exact same substances as regular/ synthetic pesticides. So it is nigh impossible to avoid chemicals/”perceived harmful substances”

Acetone dissolves the polymer, allowing the gas of the forming agent to escape. The polymer collapses on itself and becomes dense, as the gas has been removed. The polymer rearranges itself and becomes more dense.

a. lacks the required strength
b. it allows for sufficient flexibility

No. For plastic, the molecules are aligned parallel to one another, in the direction of the pull. There are weak forces/attraction between the molecules, allowing them to slide across one another, although the process is not reversible and the bag will tear eventually. The paper will tear instead of stretch since the molecules in paper are held rigidly in place and are not aligned

a. bio compatible (non-soluble + non reactive to bodily fluids), non toxic, stable, cheap, tiny pore size sufficient for water vapour to pass through.

b. polymethylmethacrylate (PMMA) and polyacrylamide/silicon based polymer. Properties include transparency, flexibility, low density, tough, unreactive, lets oxygen pass through, cheap, non-toxic, durable, comfortable.

c. Hard–> PMMA (hard, rigid, not comfy. Does not let oxygen pass through. Does not contain nitrogen atoms
soft–> polyacrylamide/silicon based (similar to the polymers/silicon based. Used to make acrylic fibres for fabrics. It absorbs water, making it more flexible and comfortable for the wearer.

They can differ in terms of the number of neutrons (eg Carbon 12 and Carbon 13) and electrons.

Carbon atoms and uranium atoms differ in terms of the number of protons, neutrons and electrons. this would endow each of the carbon atoms and uranium atoms with different chemical properties.

Instead of just a chemical symbol N, 14N and 15N represents the isotopes of nitrogen with the mass number of 14 and 15 respectively.

a. 94 protons
b. Neptunium and plutonium
c. 86

a. control rod assembly
b. cooling water out of the core
c. control rods
d. cooling water into the core
e. fuel rods

They can differ in terms of the number of neutrons (eg Carbon12 and Carbon 13) and electrons.

Carbon atoms and uranium atoms differ in terms of the number of protons, neutrons and electrons. this would endow each the carbon atoms and uranium atoms with different chemical properties.

Instead of just a chemical symbol N, 14N and 15N represents the isotopes of nitrogen with the mass number of 14 and 15 respectively.

a. 94 protons
b. Neptunium and plutonium
c. 86

a. control rod assembly
b.cooling water out of the core
c.control rods
d. cooling water into the core
e. fuel rods

It is an extremely expensive process, not to mention the huge amount of energy required. The entire process yields a less than desirable amount of potable drinking water, all in all, desalination is an unsustainable and inefficient technique in producing potable water. Desalination is also shunned because of the environmental costs (wanton disposable of concentrated wastes impacting the local ecosystems) and the exacerbation of greenhouse gas emissions (from the large energy demand) generated.

Water soluble vitamins are polar and fat soluble vitamins are non polar. “Like” dissolves “Like”, in essence, polar molecules will combine with other polar molecules and vice versa. Water, being polar, is naturally able to dissolve its polar counterpart- the water soluble vitamin. Fat soluble vitamins are not polar, because they contain mostly Carbon and Hydrogen.

a. By hanging your laundry, you reduce the need to use the dryer. As dryer consumes electricity, the reduction of use of dryer can help reduce the use of electricity. Since electricity is produced via the burning of fossil fuel, hanging your laundry out to dry can indirectly help to reduce the emission of oxides of sulfur, which causes acid rain.

b. Walking, biking, or taking public transportation to work can help to reduce the emission of oxides of nitrogen. This is because the high temperature in car engines causes the combustion of nitrogen which produces oxides of nitrogen. With the reduction of usage of fuel dependent vehicles, the amount of oxides of nitrogen produced will decrease. Hence, a reduction in an acid rain occurrence.

c. Such activities reduces the consumption of electricity. Since electricity is produced via the burning of fossil fuel, reducing the consumption of electricity can indirectly help to reduce the emission of oxides of sulfur, which causes acid rain.

d. Adding extra insulation enables one to reduce on electricity during winter. Hot water heaters consumes electricity, but extra insulation would mean that the usage of such heating equipment is less frequent. Since electricity is produced via the burning of fossil fuel, reducing the consumption of electricity can indirectly help to reduce the emission of oxides of sulfur, which causes acid rain.

e. Buying locally grown produce goes a long way in reducing pollutants from trains, planes, trucks etc with the decline in shipping overseas produce. With the reduction of usage of fuel dependent vehicles, the amount of oxides of nitrogen produced will decrease. Hence, a reduction in an acid rain occurrence.

a. The coal fired plants release huge volume of water vapour in the combustion process. The water vapour is eventually cooled in the hilly forest, which gradually becomes visible, resembling fog, decreasing visibility. Additionally, SO3 is released in the combustion process, these cluster to form small droplets, creating smog, further reducing visibility.

b. Assume that the natural pH is 7.
When the acidic level is 10 times stronger => this corresponds to a decrease by 1 pH.
So the new pH is 6.

(a) exothermic- a charcoal briquette releases heat as it burns
(b) endothermic- water absorbs the heat necessary for evaporation from your skin, and your skin feels cooler.
(c) endothermic- ice absorbs the necessary heat to melt from the environment.

weak bond strengths for reactants, strong bond strength for products, and in doing so, the overall reaction becomes a very exothermic one. Less energy is taken in to break weak bonds, and more energy released to form strong bonds.

Heat is the energy that flows from a hotter to a colder object; consequence of motion at the molecular level. Temperature determines the direction to which heat flows (degree of hotness and coldness); average speed of that motion.

Heat from the fire cooks the food.
Temperature is the measurement of the day’s weather, and it tells us of the degree to which the temperature changes at different time intervals.

(a) It has a knocking characteristic of 98% isooctane, and 2 % hectane, which makes it 98% resistant to knocking, which is great.
(b) No, if there is a need to find out, we can’t be looking purely at octane ratings.