Cloning merely provides a copy of the previous dog breed whereas breeding provides the chance of improvement.

The two pros include : Solving temporary problem of the country in crisis, reduce the need for huge manpower labour. The two cons include : potential harm to the ecosystem as by removing one pest that harms the crop, one is removing the food source for the animal. And there could be a possible emergence of new diseases since the GM corn is modified using bacteria and viruses.

a) CnH2nOn = Cn(H2O)n
c) Yes, different isomers will have different sweetness. Isomers may have the same molecular formula, but they are structured differently, resulting in different chemical structure and properties.
As such, the sweetness between the isomers will not the same. One pair of example would be glucose and fructose.

All organic food contains chemicals naturally, so it is impossible to go chemical-free even if you do eat only organic food stuff.

Similar example : moisture-free water

When Styrofoam is produced, hot air is blown into the polymer and to expand to 40 to 50 times the original size of the polymer. Therefore it contains a lot of air. When Styrofoam is dissolved in acetone, the air will be released and once the acetone is evaporated, the original polymer is left behind without the air.

A. Branched LDPE is not as strong as a material compared to linear HDPE.

B. It has a crystalline structure = higher density, stronger attraction force between molecules, overall stronger than LDPE. So the material will not break and you will not currently yourself.

No. Paper is made up of cellulose, a natural polymer, which is held together by strong hydrogen bonds. It has higher tensile strength and is less ductile/more brittle. Plastic bag is made up of LDPE and the long polymer chain has more allowance for shearing and the plastic stretches instead of breaking immediately.

A. Flexible, insolubility, non-toxic and inert

B. Hard – methyl methacrylate (PMMA)
Soft – hydroxylethyl methacrylate (polycrylamide)

Properties : transparent, flexible, low density, unreactice to chemicals on the surface, easy to manufacture, hydrophilic, permeable to Oxygen, tough.

C. Polycrylamide contains nitrogen atoms. Similarly to polymers to make acrylic fiber for fabrics. When Polycrylamide is cross-linked, the material absorbs water which keeps them less soft and flexible.

1. Number of neutrons (different isotopes)
2. Different ions (different in charge)

1. Half-life
2. Number of valence shells
3. Chemical reactions associated with the atoms

N is simply the chemical symbol.
14N and 15N have same number of protons and electrons. The only difference is the number of neutrons.

a) 94
b) Np: 93 Neptunium
Pu: 94 Plutonium
c) 86

E
D
B
A
C

Desalination requires high energy consumption to boil the mixture and separate the water from salt. The overall yield of potable water is also not very high. It is very expensive to build the desalination plant and the process produces a lot of waste.

‘Like dissolves like.’ Water-soluble vitamins are polar. They have a positive charge at one end and a negative charge at the other while fat-soluble vitamins do not. They have more polar than non-polar groups this mixing with polar water molecules. Fat-soluble vitamins are non-polar. They have few or no polar groups this blending with non-polar lipids. Water in this case is the polar solvent while fats would be a non-polar solvent.

Save electricity and burning of coal for energy:
a. Save the use of a dryer
b. Reduce production of NO2
c. Saving water and energy
d. Saving energy needed for continual heating
e. Reduce production of NO2 from transporting of food

a. By burning more coal, there will be more air pollutants and smoke in the air closer to the plant. This will affect the visibility since the particles will reflect light and lower visibility.
b. Normal pH of rain is 5.3. For every pH the acidity will change by 10times. So if the rain is 10times more acidic, the pH will be 5.3-1=4.3

a. Exothermic, burning gives off heat energy.
b. Endothermic, during evaporation water takes in heat energy and skin feels cooler.
c. Endothermic, during melting ice absorbs heat energy though there’s no change in temperature.

Initial reactant bond strength has to be weak while product bond strength has to be strong to lead to an exothermic reaction. Reactant bond strength is relatively much weaker than product bond strength so that it can be highly exothermic enough to be explosive. Gases are more reactive than solids or liquids due to their weaker bonds.

Heat: total energy (kinetic + potential) possessed by molecules in a piece of matter, measured in joules, and has the ability to do work.
Temperature: not energy, measured in Kelvin, can only be used to measure the hotness or coldness of something.
Eg, during melting, there is no change in temperature, but there is transfer of heat from the surroundings to the ice.

a. It has high anti-knocking characteristics. Higher rating means better for the engine.
b. We do not know. Rating simply corresponds to knocking characteristics and is used as a form of comparison between types of gasoline.