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The general formula for the alkyne homologous series is C\(_n\)H\(_{2n−2}\), where n is the number of carbon atoms. The first member of the series has n=2 (ethyne), as a minimum of two carbon atoms is required for a triple bond. The 5th member of the alkyne series is hexyne (C\(_6\)H\(_{10}\)).

The empirical formula is defined as the chemical formula that represents the simplest whole-number ratio of the atoms of each element present in a compound. For this reason, it is also frequently referred to as the simplest formula.

The activation energy is the energy required to get the reaction going. It's the difference between the energy of the reactants and the peak of the hump.

The effect of pressure on a chemical system at equilibrium is only on gaseous substances. We'll need to consider the number of moles of the gaseous substances on the LHS as well as the total number of moles of the gaseous substances on the RHS. The side with the lower total number of moles will be favoured by an increase in pressure and vice versa. However, since the number of moles of the gaseous substances on both sides are 1, i.e they are equal, an increase in pressure has no effect on the chemical system in equilibrium.

The question can be explained by Graham's law of diffusion. According to this law, under the same conditions of temperature and pressure, the rate of diffusion of a gas is inversely proportional to the square root of its molar mass. \(\frac{R_x}{R_y}\) = \(\sqrt{\frac{M_y}{M_x}}\) From the question, Gas X diffuses twice as fast as gas Y i.e x = 2y This implies x =2 while y = 1 From \(\frac{R_x}{R_y}\) = \(\sqrt{\frac{M_y}{M_x}}\) \(\frac{2}{1}\) = \(\sqrt{\frac{M_y}{M_x}}\) \(\frac{4}{1}\) = \(\frac{M_y}{M_x}\) M\(_y\) = 4 M\(_x\) ⇒ Gas Y is 4 times as heavy as Gas X. - Option B

To find the number of molecules, we'll use the formula: Number of moles = \(\frac{Number of molecules}{Avogadro number}\) But We were only given the mass of Helium = 11.5g , knowing the atomic mass or molar mass of He = 4 g/mol Number of moles = \(\frac{mass}{molar mass}\) = \(\frac{11.5}{4}\) = 2.875 moles Number of molecules = Number of moles x Avogadro number = 2.875 x 6.02 x 10\(^{23}\) = 17.3075 x 10\(^{23}\) = 1.73 x 10\(^{24}\)

Alnico is ferromagnetic, meaning it can be used to make permanent magnets. Alnico is an iron alloy with the acronym "al-ni-co" that's made up of aluminum (Al), nickel (Ni), and cobalt (Co). Option B

Gold and silver are noble metals, because they are resistant to corrosion and oxidation, even at high temperatures. Noble metals are a group of metals that are less reactive than other metals and are not easily corroded or oxidized.

Aluminum is extracted from bauxite by electrolysis. The extraction proceeds in two stages; 1. Purification of the Bauxite: The impure bauxite is heated with sodium hydroxide solution to form soluble sodium tetrahydroxy aluminate (iii). The impurities in the ore which are iron (iii) oxide and trioxosilicate (iv) compounds are not soluble in the alkali. They are therefore filtered off as a sludge. Aluminum hydroxide crystals is then added to filtrate, NaAl(OH)\(_4\) solution to induce the precipitation of Aluminum hydroxide. 2. The electrolysis of the pure alumina

In contact with water, calcium carbide instantly decomposes hydrolytically, yielding acetylene gas and calcium hydroxide. Calcium ethynide is also known as calcium carbide. CaC\(_2\) + 2H\(_2\)O → Ca(OH)\(_2\) + C\(_2\)H\(_2\)

Bitumen is the petroleum product which is used for surfacing roads. It is also known as asphalt. It is used as an alternative for coal-tar.​

The petroleum fractions that distill at 200–250^\circC are naphtha and kerosene, Bitumen: has a boiling point value of 525\(^0\)C Gasoline: Has a boiling range of 40–200^\circC Diesel: Has a boiling range of 250–350^\circC Fuel oil, paraffin, lubricants: Have a boiling range of 300–370^\circC Residue, crude oil: Has a boiling point of more than 370^\circC

Coal tar is a known human carcinogen. It contains potent carcinogens like benzo(a)pyrene, benz(a)anthracene, and dibenz(a,h)anthracene. Fractional distillation of coal tar is a process that produces aromatic hydrocarbons like benzene, creosotes, naphthalene, anthracene, carbolic and cresylic acids, pyridine, and pitch. Benzene is used in the pharmaceutical industry as a solvent and in the synthesis of drugs such as cyclohexane, phenol etc.Thus the correct answer is option B- Benzene

C H N O \(\frac{53.1}{12}\) \(\frac{6.2}{1}\) \(\frac{12.4}{14}\) \(\frac{28.3}{16}\) \(\frac{4.425}{0.886}\) \(\frac{6.2}{0.886}\) \(\frac{0.886}{0.886}\) \(\frac{1.769}{0.886}\) 5 : 7 : 1 : 2 C\(_5\) H\(_7\) N O\(_2\) - Empirical formula (Empirical formula) n = Molecular formula (C\(_5\)H\(_7\)NO\(_2\))n = 2 x vapour density ([12x5] + [1x7] + 14 + [16x2] ) n = 2 x 56.5 113n = 113 n = \(\frac{113}{113}\) n = 1 Therefore, the molecular formula is C\(_5\)H\(_7\)NO\(_2\)

Empirical formula of organic liquid is XY (Empirical formula) x n = 2 x Vapour density (XY) = 2 V.D (72 + 6) = 2 V.D 78 = 2 V.D V.D = \(\frac{78}{2}\) V.D = 39