Correct Answer: D. highly acidic

Correct Answer: B. Polymerization

Correct Answer: C. Legislature

Explanation

(a) Explanation of chemical weathering of rocks:

Chemical weathering is the decomposition of rocks by chemical agents formed through the reaction of water with atmospheric gases such as air (oxygen and carbon dioxide) As some minerals in the rocks are dissolved and others change into new chemical products therefore disintegration of rocks occurs.

(b)Discussion of chemical weathering of rocks (Any four)

Hydration

Occurs when water combines with or binds to some minerals Intact water may bind to silicates, oxides of iron

Hydrated compounds are soft and easily fragmented It does not usually affect the chemical composition of the hydrated product

Example of hydration reaction are

Fe203 + 3H20 → . Fe203.3H20

Haematite Limonite/Hydrated Haematite (Yellow)

(Red)

OR

CaSO4 + 2H20 → CaSO4 .2H20

(Calcium Sulphate) (Gypsum)

OR CuS04 + 5H20 → CuS04. 5H20

(Anhydrous Copper Sulphate)Carbonation (Hydrated Copper II sulphate )/Blue stone/

Carbonation

This is brought about by the combination of carbonate (C02-3) or bicarbonte (HCO-3) ions with rock minerals

The carbon dioxide released to the atmosphere from various sources combines with water/rainwater to form carbonic acid

C02 + H20 →← H2C03

The carbonic acid attacks the minerals and C02 in the rock.

In limestone or marbles the calcite present is dissolved.

CaCO₃ + H₂CO₃ → Ca(HCO₃)₂ →

Oxidation/Reduction

Atmospheric oxygen and free oxygen in rain water carry out this reaction

Minerals containing iron (Ferrous form), manganese and sulphur are the ones most frequently affected by this reaction

When they are exposed to air and water, the ferrous ion is oxidized to the ferric Fe2 + state.

The change in valency from Fe ++ to Fe + destabilizes the molecule and leads to disintegration

4Fe C03 + 02→ 2Fe203 + 4C02

Iron (II) Oxygen Iron Oxide Carbon dioxide

carbonate

Hydrolysis

A decomposition reaction in which silicate minerals are broken down Water molecule is split into H+ and OR ions

H₂0 + H⁺ → HO^-

The H+ replaces the cation from the mineral structure while the mineral is released for plant uptake

Example:

CaSi03 + 2H20 → H2Si03 + Ca(OH)2

Calcium silicate water

Correct Answer: B. rejection of fabrications

Correct Answer: B. a council chamber

Correct Answer: D. quantity damanded

Explanation

A change in quantity demanded refers to a change in the specific quantity of a product that buyers are willing and able to buy usually caused by a change in the price. From the question above, a rise in prise led to a corresponding change in the quantity demanded from 250 to 200 units.

Correct Answer: C. jupiter

Correct Answer: D. 11

Correct Answer: A) Parasitism

Explanation

In Biology, organisms often have relationships with each other, and one such relationship is called symbiosis. Symbiosis is a relationship in which two or more organisms closely interact with each other. One type of symbiotic relationship is called parasitism. In parasitism, one organism benefits at the expense of the other organism, which is harmed. In this relationship, the organism that benefits is called the parasite, and the organism that is harmed is called the host. In the context of the question, a symbiotic relationship in which one organism is completely dependent on another organism is called parasitism. This means that the dependent organism, the parasite, cannot live without the other organism, the host. The host provides the parasite with food and shelter, while the parasite harms the host. The other options listed in the question are commensalism, mutualism, saprophytism, and competition. Commensalism is a type of symbiotic relationship where one organism benefits and the other is neither helped nor harmed. Mutualism is a symbiotic relationship where both organisms benefit. Saprophytism is a relationship where one organism feeds on dead or decaying matter. Competition is a relationship where two organisms compete for the same resources. Therefore, the correct answer to the question is option A: Parasitism.