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Hybridization is the process of mixing orbitals with slightly different energies to create new orbitals with the same shape and energy. In ethyne, each carbon atom's 2s orbital combines with one of its 2p orbitals to form two sp hybrid orbitals. Ethyne, also known as acetylene, has sp hybridization

A dehydrating agent is a substance that dries or removes water from a substance. so when sulphuric acid with sugar, the sugar is charred by the removal of water, \(C_{12}H_{22}O_{11(s)} + H_2SO_{4(aq)} → 12C(s) + 11H_2O_{(l}) + H_2SO_{4(aq)}\) the sulphuric acid is serving as a dehydrating agent.

Sodium reacts vigorously with water to produce a solution of sodium hydroxide and hydrogen gas. Sodium hydroxide is an alkali. 2Na + 2H\(_2\)O → 2NaOH + H\(_2\)

Cl is diatomic; 4\(Cl_2\) = 8 atoms in total. Oxygen is triatomic in Ozone; 3\(O_3\) = 9 atoms in total Butane is \(C_4H_{10}\) = 14 atoms in total. Argon is monoatomic; = 7atoms. hence Option D is correct.

From the solubility curve given, if you extrapolate for solution L at 60\(^0\)C and 25\(^0\)C, the solubility values will be 1.5 moldm\(^{-3}\) and 0.75 moldm\(^{-3}\) respectively. To determine the amount in mole that will separate out, subtract the solubility of the initial temperature 25\(^0\)C from that of the final temperature 60\(^0\)C. i.e 1.5 - 0.75 = 0.75 - Option A

If the gas is cooled, the temperature at which it will start to condense will be the distance between the liquid and vapour from the graph. Extrapolate to the y-axis(Temperature axis), you'll discover it's around 150\(^0\)C. The temperature at which water vapour in the air starts to condense is referred to as the dew point.However,condensation will occur when the water vapour in the air is cooled, changing from gas to liquid.

Melting involves change of state from solid to liquid. From the graph, check the interval from solid to liquid, it begins from 0 and ends at 2.5mins. Option A is the answer

Covalent bonds involve the sharing of electrons between two atoms

From the solubility curve given, if you extrapolate for solution L at 60\(^0\)C and 25\(^0\)C, the solubility values will be 1.5 moldm\(^{-3}\) and 0.75 moldm\(^{-3}\) respectively. To determine the amount in mole that will separate out, subtract the solubility of the initial temperature 25\(^0\)C from that of the final temperature 60\(^0\)C. i.e 1.5 - 0.75 = 0.75 - Option A

The passage describes how the rise of motor vehicles (cars, lorries, and motorcycles) led to changes in road transport, such as the adaptation of road surfaces through tar-spraying and efforts to widen and straighten roads. Although challenges remained, these adjustments indicate an overall improvement in road transport systems.

The expression "unless mechanically minded" refers to coachmen and grooms who would struggle to adapt to the new technology of motor vehicles. In other words, only those are can adapt to new technology would be able to continue making a living, as the rise of motor vehicles was making traditional roles like that of coachmen and grooms obsolete.

The association between the root nodule of a leguminous plant and rhizobium sp is a symbiotic relationship that benefits both the plant and the bacteria. Rhizobium bacteria are soil bacteria that infect the roots of leguminous plants and cause the formation of nitrogen-fixing nodules. The bacteria convert atmospheric nitrogen into ammonia, which the plant can use for growth and development. Leguminous plants on the other hand with their plant roots provide food to the rhizobia in the form of carbohydrates, such as malate and succinate. Mycorrhiza is a symbiotic relationship between the roots of plants and fungi that benefits both organisms.

Amphibians are mostly semi-aquatic and spend part of their time on land and part in water. They typically start out as larvae living in water, but some species have developed behavioural adaptations to bypass this. Amphibians require moist habitats, and relative humidities of about 80% work well for most species. Hence, they live in water as well as a moist land. Option B

Among animals, viviparity is development of the embryo inside the body of the parent, eventually leading to live birth, as opposed to reproduction by laying eggs that complete their incubation outside the parental body. This is found mainly in mammals.

The Antennae are sensory organs that are made up of one or more jointed segments and are attached to the first one or two segments of the insect's head. Insects have paired antennae so they can smell in stereo. The jointed structure in insects that bears organs sensitive to touch, smell, and vibration is the antennae