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When sulphur dioxide (SO₂) reacts with an acidified solution of potassium permanganate (KMnO₄), the initially purple solution turns colourless. The reason is because the reaction between SO₂ and KMnO₄ is a redox (reduction-oxidation) reaction. SO₂ acts as a reducing agent, meaning it causes the reduction of another substance (KMnO₄), While the permanganate ion (MnO₄⁻) in KMnO₄ is reduced to manganese(II) ions (Mn²⁺), which are colourless. SO₂ is oxidized to sulphate ions (SO₄²⁻), which are also colourless. So, the purple colour of KMnO₄ is due to the permanganate ion, and when this ion is reduced, the solution becomes colourless.

The activation energy, Ea is the energy of the transition state, (T.E) minus the reactant energy (R.E). For Catalyzed reaction, Ea = T.E - R.E = 45 - 15 = 30 For Uncatalyzed reaction, Ea = T.E - R.E = 50 - 15 = 35

When chlorine water (a solution of chlorine gas in water) is exposed to sunlight, chlorine reacts with water molecules to form hypochlorous acid (HClO), which then decomposes into hydrochloric acid (HCl) and oxygen gas (O\(_2\)). Initial Reaction: Cl₂ + H₂O ⇌ HClO + HCl Decomposition of Hypochlorous Acid: HClO → HCl + [O] (nascent oxygen) Formation of Oxygen Gas: [O] + [O] → O₂ Overall Reaction: 2Cl₂ + 2H₂O → 4HCl + O₂ N.B: Nascent oxygen refers to the atomic form of oxygen (represented as [O]) that is highly reactive and unstable.

2NH₄Cl + Ca(OH)₂ → CaCl₂ + 2NH₃ + 2H₂O The reaction between ammonium chloride and calcium hydroxide is a double displacement reaction. However, in the reaction between ammonium chloride (NH₄Cl) and calcium hydroxide (Ca(OH)₂), quicklime (CaO) is used to dry the ammonia gas (NH₃) produced by absorbing water, preventing the formation of ammonium sulphate when sulphuric acid is used to dry the gas.

The compound above is Butan-2-ol or 2- butanol. Oxidizing butan-2-ol (a secondary alcohol) yields butan-2-one (also known as methyl ethyl ketone or 2-butanone), a ketone. In summary, when primary alcohols are oxidized, they can form aldehydes or carboxylic acids, depending on the reaction conditions and the strength of the oxidizing agent used. When secondary alcohols are oxidized, they form ketones. Tertiary alcohols are generally not readily oxidized under typical conditions, and they do not form aldehydes, ketones, or carboxylic acids. The reason is because the carbon atom attached to the hydroxyl (-OH) group in a tertiary alcohol is already bonded to three other carbon atoms. This means there are no hydrogen atoms available on that carbon for oxidation to occur.

The structure of 2-methylbut-2-ene in in option D.The Carbon, carbon double bond is on C-2 with a substituent group,Methyl (CH\(_3\)) also on C-2 with the parent name being but-2-ene, since the longest carbon chain is four and the double bond is on carbon 2.

When a carboxylic acid (RCOOH) reacts with sodium bicarbonate (NaHCO\(_3\)), it forms a salt (RCOONa), water (H\(_2\)O), and carbon dioxide (CO\(_2\)). The carbon dioxide gas produced in this reaction is what causes the bubbles or effervescence observed. RCOOH + NaHCO\(_3\) → RCOONa + H\(_2\)O + CO\(_2\) This reaction is a simple and reliable test to distinguish carboxylic acids from other organic compounds, as most other functional groups (like alcohols or phenols) are not acidic enough to react with bicarbonate and produce a gas.

The activation energy, Ea is the energy of the transition state, (T.E) minus the reactant energy (R.E). For Catalyzed reaction, Ea = T.E - R.E = 45 - 15 = 30 For Uncatalyzed reaction, Ea = T.E - R.E = 50 - 15 = 35

pronounciation

A deficiency in vitamin E can lead to hemolytic anemia and neurological deficits. Night blindness can be caused by a deficiency in vitamin A. Vitamin A is essential for the production of pigments in the retina that help you see in low light. Vitamin K is essential for the production of proteins that help the blood clot, and a deficiency leads to impaired coagulation. A major disease caused by severe vitamin C deficiency is scurvy. Scurvy is a disease caused by a severe and prolonged deficiency of vitamin C, leading to symptoms like fatigue, bleeding gums, skin hemorrhages, and impaired wound healing.

Water is a product of excretion common to the kidneys, lungs, and skin in mammals, although it is excreted in different forms and quantities by each organ. Kidneys:The kidneys excrete water as a component of urine, along with other waste products like urea and salts. Lungs:The lungs excrete water in the form of water vapour during exhalation, along with carbon dioxide. Skin: The skin excretes water through sweat, which also contains salts and other waste products.

As the diaphragm and intercostal muscles relax, the lungs and thoracic tissues recoil, and the volume of the lungs decreases. This causes the pressure within the lungs to increase above that of the atmosphere, causing air to leave the lungs.Muscle contraction and relaxation are not the same; contraction is the tightening or shortening of muscles, while relaxation is the return of the muscle fibers to a low-tension state.

The nervous and endocrine systems both play crucial roles in maintaining homeostasis and coordinating bodily functions by using chemical signals to communicate and respond to stimuli, but they differ in their speed and duration of response. The nervous system uses electrical and chemical signals (neurotransmitters) to transmit information rapidly, while the endocrine system uses chemical messengers (hormones) that are released into the bloodstream.

The heart is the organ located in the pericardial cavity of a mammal. The pericardial cavity is a sac that surrounds the heart and contains a small amount of fluid. In mammals, the pericardial cavity, a space surrounding the heart, is located within the mediastinum, a region of the thoracic cavity, specifically between the lungs and sternum.

The presence of a vertebroarterial canal (also known as the foramen transversarium) in the transverse processes is a unique characteristic of cervical vertebrae, specifically for the passage of the vertebral artery and vein.