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this question expresses the law of multiple proportions which states that if two elements A and B combine together to form more than one compound, the various masses of element B which combines with a fixed mass of B are in simple whole number ratios. e.g

- potassium chlorate --> KClO\(_3\) valencies of K = +1, O = -2. : (+1) + Cl + ( -2 X 3 atoms ) = 0 Cl + 1 - 6 = 0 Cl = 5 ∴ The oxidation state of chlorine in potassium chlorate is +5

- Alkaline solutions of pyrogallol absorb oxygen efficiently. - Quicklime have a strong chemical affinity to absorb water. - At room temperature, Calcium oxide (CaO) will spontaneously absorb carbon dioxide from the atmosphere.

No expanded working has been attached for this question yet. The verified answer is Option D.

The process described is called cracking. When large hydrocarbon molecules are heated to high temperatures, often in the presence of a catalyst, they break down into smaller, more useful molecules. This process is crucial in the petrochemical industry for converting heavy fractions of crude oil into lighter, more valuable products like gasoline and fuel oil.

W is the most acidic solution since 4 < 6 < 8 < 10. The lower the value on the pH scale, the more acidic a solution.

When heated, the nitrates of potassium, magnesium, and iron decompose as follows: - Potassium nitrate (KNO₃) decomposes to potassium nitrite (KNO₂) and oxygen (O₂). - Magnesium nitrate (Mg(NO₃)₂) decomposes to magnesium oxide (MgO) and nitrogen dioxide (NO₂) and oxygen (O₂). - Iron(III) nitrate (Fe(NO₃)₃) decomposes to iron(III) oxide (Fe₂O₃) and nitrogen dioxide (NO₂) and oxygen (O₂). So, all three nitrates would not decompose to their respective oxides except Nitrates of Magnesium and Iron. The correct answer is C.

Copper cannot replace hydrogen from water or steam because it is less reactive than hydrogen and therefore cannot displace it in a chemical reaction. Copper is located below hydrogen in the reactivity series, indicating that it is less reactive and cannot displace hydrogen.

No expanded working has been attached for this question yet. The verified answer is Option D.

Cu\(^+\) is discharged preferentially at the cathode OH\(^-\) is discharged preferentially at the anode The presence of SO\(_4\)\(^2-\) and H\(^+\) makes the medium acidic Which makes the litmus turns red and oxygen is evolved

Esterification, a reaction in which a carboxylic acid and an alcohol, heated in the presence of a mineral acid catalyst, form an ester and water:

The IUPAC id for \(CH_{3}COOH\) is Acetic acid, while for \(C_{2}H_{4}\) is ethene.

According to Graham's law of diffusion of gases,the rate of diffusion of a gas is proportional to the square root of the density. From the question, the given parameters are: Volume of Oxygen, V\(_o\) = 30cm\(^3\), Time of diffusion of Oxygen, t\(_o\) = 7s, Vapour density of Oxygen, d\(_o\) = 16 Volume of Chlorine, V\(_c\) = 60cm\(^3\), Time of diffusion of chlorine, t\(_c\) = ?, Vapour density of Chlorine, d\(_c\) = 36 \(\frac{t_o}{t_c}\) = \(\sqrt{\frac{d_o}{d_c}}\) \(\frac{7}{t_c}\) = \(\sqrt{\frac{16}{36}}\) \(\frac{7}{t_c}\) = \(\frac{4}{6}\) t\(_c\) = \(\frac{7}{4}\times {6}\) t\(_c\) = \(\frac{21}{2}\) Recall that the volume of Chlorine is twice that of Oxygen. Hence, t\(_c\) = 2t\(_o\) t\(_c = 2\times \frac{21}{2}\) t\(_c\) = 21sec - Option C

No expanded working has been attached for this question yet. The verified answer is Option C.

No expanded working has been attached for this question yet. The verified answer is Option E.