Group 2

Group 02 Group Name : Group 2
Group Members :
1.

a. C6H12O6 = C6(H2O)6
b. (refer to hard copy)
c. No. Fructose is sweeter than glucose even though they have the same molecular formula, but due to different structural formulas, they have different properties and different sweetness.

2.

There are many chemical pollutants in the air which may be carried by wind across the globe, and be dissolved in the rain or bodies of water used to irrigate ‘organic’ crops. Everything has chemical compounds in it.

3.
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9.
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10.
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Group 2

Group 02 Group Name : Group 2
Group Members :
1.

When the polystyrene comes into contact with acetone, it acts as a molecular lubricant allowing the polymer chains to slide around each other hence, the styrofoam becomes soft and releases the air bubbles, consequently resulting in a denser polystyrene solid.

2.

a. It does not have the required strength to resist a cut
b. The HDPE molecules must line up in a way that they provide the correct amount of strength/resilience, using a thin liner of HDPE allows sufficient flexibility while still being strong.

3.

No, paper does not stretch.
For the plastic bag, there are the weak but extensive dispersion forces also allow the molecules to slip pass one another allowing the plastic to stretch and “neck”. When force is applied to a piece of paper, it results in a tear instead of stretching. This is because the cellulose molecules of the paper are held far more rigidly in place and are not free to become aligned.

4.

a. resistant to corrosion, durable, non-toxic, inert, semi-permeable (allowing essential materials to diffuse allowing for material transport).
b. semi-rigid gas permeable polymers (e.g. polymathy methacrylate). Transparent, low density, inert, easy to hold, hydrophilic, allows oxygen to pass through.
c. Hard contact lenses are not oxygen permeable, while soft contact lenses are. The use and formulation will be different. Structure, branching and linearity affect the ease of wearing contact lenses

5.
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6.
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7.
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8.
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9.
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10.
[311]

Group 2

Group 02 Group Name : Group 2
Group Members :
ANG YU TING, RIA CHEN LISHAN, XIE WENHAN, CHEN XIYAN, TAN HUI SIN, AMEER S/O ANAITH ALI
1.

They can differ in number of neutrons (forming isotopes), and in the number of electrons.
For instance for isotope: C-12 Vs C-14
For the way they differ in the number of electrons: C+ Vs C Vs C-.

Carbon vs. Uranium atoms
– different number of protons
– different number of neutrons
– different number of electrons

2.

The symbol N represents the element nitrogen and stands for the naturally occurring mixture of all isotopes, hence symbols 15N and 14N are isotopes of the same element – consequently they have different mass numbers of 15 and 14 respectively.

3.

a. 94 protons
b. Np (Neptunium) and Pu (Plutonium)
c. 86 protons

4.

E- fuel rods
D- cooling water into the core
B- cooling water out of the core
A – control rod assembly
C- control rods

5.
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6.
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7.
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8.
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9.
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10.
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Group 2

Group 02 Group Name : Group 2
Group Members :
1.

High energy impact, which relates to high cost of operation, as well as increased burning of fossil fuels. Making it less competitively priced that other alternatives.

2.

Water soluble vitamins are polar compounds, while fat soluble vitamins are non polar.
Applying the ‘like dissolves like’ principle. For instance, water soluble vitamins are only able to dissolve in polar solvent such as water while fat soluble vitamin are only able to dissolve in non-polar solvent (organic solvent) such as hexane. QED.

3.

(a) Dryers are major consumers of electricity in the home. Hence, hanging laundry out to dry reduces the amount of electricity consumed, which in turn reduces reduces the burning of fossil fuels, consequently reducing SOx and NOx and acid rain.

(b) Reducing production of SOx and NOx.

(c) Dishwashers are major consumers of electricity in the home. Hence, not using the dishwasher reduces reduces the burning of fossil fuels, consequently reducing SOx and NOx and acid rain.

(d) Reduce heat loss, hence reducing the amount of electricity consumed, which in turn reduces reduces the burning of fossil fuels, consequently reducing SOx and NOx and acid rain.

(e) Reducing Air and sea transportation for produce by buying local produce reduces the burning of fossil fuels, consequently reducing SOx and NOx and acid rain.

4.

Coal fired electricity unitility plans produce hight amounts of SOx , which will be converted to Sulphuric acid when in contact with water vapour in the atmosphere and remains suspended. This reflects lights hence causing poor visibility and acid rain.

pH about 4.3.

5.
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7.
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8.
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9.
[259]
10.
[261]

Group 2

Group 02 Group Name : Group 2
Group Members :
Tan Hui Sin, Ria Chen Lishan, Ang Yu Ting, Xie Wenhan, Ameer S/o Anaithali, Chen Xi Yan
1.

a. Exothermic: combustion gives off heat
b. Endothermic:removes latent heat of evaporation from our skin and cools surface temperature (energy is used to change water from liquid to gaseous state)
c. Endothermic:Energy is absorbed to break Intermolecular forces of attraction.

2.

Energy for bond forming is much greater than energy for bond breaking.
Bond energy of products are much higher than the bond energy of reactants.

3.

Temperature is like a measurement. Heat is the total energy of molecular motion.
For example the temperature of a small cup of water may be the same as the temperature of a large tub of water, but the tub of water has more heat because it has more water, thus it has more thermal energy.

4.

a. There are low knocking characteristics – 98% isooctane, 2% heptane
b. It doesn’t tell us that it contains oxygenates.

5.
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10.
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