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Which of the following represents the saponification reaction? (a) CH3COONa + NaOH CH4 + Na2CO3 (b) CH3COOH + C2H5OH CH3 COOC2H5 +H2O (c) 2CH3COOH + 2Na → 2CH3 COONa + H2 (d) CH3COOC2H5 + NaOH → CH3 COONa + C2 H5OH

Answer: (d) CH3COOC2H5 + NaOH → CH3COONa + C2H5OH Saponification is the process of preparation of soap. The reaction does not require heat... View Article

The heteroatoms present in CH3 — CH2 — O — CH2— CH2 Cl are (i) oxygen (ii) carbon (iii) hydrogen (iv) chlorine a) (i) and (ii) (b) (ii) and (iii) (c) (iii) and (iv) (d) (i) and (iv)

Answer: (d) (i) and (iv) In organic chemistry, heteroatoms are the ones that are not carbon or hydrogen. Molecules formed by only one type of... View Article

The name of the compound CH3 — CH2 — CHO is (a) Propanal (b) Propanone (c) Ethanol (d) Ethanal

Answer: (a) Propanal In propanal (CH3 — CH2 — CHO) the functional group is -CHO(aldehyde). In aldehydes, the carbonyl group has one... View Article

Which of the following does not belong to the same homologous series? (a) CH4 (b) C2 H6 (c) C3 H8 (d) C4 H8

Answer: (d) C4H8 Homologous series is a series of compounds with similar chemical properties and some functional groups differing from the... View Article

Which among the following are unsaturated hydrocarbons?

Answer: (c) (ii) and (iv) Unsaturated hydrocarbons are organic compounds that are entirely made up of carbon and hydrogen atoms and consist of a... View Article

Which of the following is not a straight-chain hydrocarbon?

Answer: (d) Because each carbon atom is linked to one or two other carbon atoms in (a), (b), and (c). Hence they are linear hydrocarbons. The... View Article

The correct electron dot structure of a water molecule is

Answer: (c) Lewis dot structures reflect the electronic structures of the elements, including how the electrons are paired. In Lewis dot... View Article

Carbon forms four covalent bonds by sharing its four valence electrons with four univalent atoms, e.g. hydrogen. After the formation of four bonds, carbon attains the electronic configuration of (a) helium (b) neon (c) argon (d) krypton

Answer: (b) neon In its innermost shell, the carbon atom has two electrons and four valence electrons. When it forms covalent bonds with four... View Article

Mineral acids are stronger acids than carboxylic acids because (i) mineral acids are completely ionised (ii) carboxylic acids are completely ionised (iii) mineral acids are partially ionised (iv) carboxylic acids are partially ionised (a) (i) and (iv) (b) (ii) and (iii) (c) (i) and (ii) (d) (iii) and (iv)

Answer: (a) (i) and (iv) Mineral acids are completely ionized whereas carboxylic acids are partially ionized. Hence mineral acids are stronger... View Article

Vinegar is a solution of (a) 50% – 60% acetic acid in alcohol (b) 5% – 8% acetic acid in alcohol (c) 5% – 8% acetic acid in water (d) 50% – 60% acetic acid in water

Answer: (c) 5% – 8% acetic acid in water Vinegar is a dilute aqueous solution of ethanoic acid. The main component of vinegar is acetic... View Article

The correct structural formula of butanoic acid is

Answer: (d) Butanoic acid is an oily colourless liquid with a chemical formula. It is a short-chain saturated fatty acid found in the form of... View Article

Ethanol reacts with sodium and forms two products. These are (a) sodium ethanoate and hydrogen (b) sodium ethanoate and oxygen (c) sodium ethoxide and hydrogen (d) sodium ethoxide and oxygen

Answer: (c) sodium ethoxide and hydrogen The reaction between sodium and ethanol has the following equation: 2CH3COOH + Na → 2CH3COONa + H2... View Article

Pentane has the molecular formula C5 H12. It has (a) 5 covalent bonds (b) 12 covalent bonds (c) 16 covalent bonds (d) 17 covalent bonds

Answer: (c) 16 covalent bonds Pentane is an organic compound that is a clear colourless liquid. It is less dense than water and is insoluble in... View Article

In the soap micelles (a) the ionic end of soap is on the surface of the cluster while the carbon chain is in the interior of the cluster. (b) ionic end of soap is in the interior of the cluster and the carbon chain is out of the cluster. (c) both ionic end and carbon chain are in the interior of the cluster (d) both ionic end and carbon chain are on the exterior of the cluster

Answer: (a) the ionic end of soap is on the surface of the cluster while the carbon chain is in the interior of the cluster. A soap molecule is a... View Article

Chlorine reacts with saturated hydrocarbons at room temperature in the (a) absence of sunlight (b) presence of sunlight (c) presence of water (d) presence of hydrochloric acid

Answer: (b) presence of sunlight The process of halogenation of hydrocarbons occurs when chlorine reacts with saturated hydrocarbons in the... View Article

Identify the unsaturated compounds from the following (i) Propane (ii) Propene (iii) Propyne (iv) Chloropropane (a) (i) and (ii) (b) (ii) and (iv) (c) (iii) and (iv) (d) (ii) and (iii)

Answer: (d) (ii) and (iii) Unsaturated hydrocarbons are organic compounds that are entirely made up of carbon and hydrogen atoms and consist of a... View Article

Structural formula of ethyne is

Answer: (a) The condenses structure formula of ethyne is HC ≡ CH. The molecular formula of ethyne is – C2H2. That means ethyne... View Article

Which of the following is the correct representation of the electron dot structure of nitrogen?

Answer: (d) Each nitrogen atom has 5 valence electrons, and there is a triple bond between the two nitrogen atoms in a nitrogen molecule. The... View Article

The soap molecule has a (a) hydrophilic head and a hydrophobic tail (b) hydrophobic head and a hydrophilic tail (c) hydrophobic head and a hydrophobic tail (d) hydrophilic head and a hydrophilic tail

Answer: (a) hydrophilic head and a hydrophobic tail A soap molecule is a sodium or potassium salt of long-chain carboxylic acid. It is composed... View Article

Oils on treating with hydrogen in the presence of palladium or nickel catalyst form fats. This is an example of (a) Addition reaction (b) Substitution reaction (c) Displacement reaction (d) Oxidation reaction

Answer: (a) Addition reaction Fats are formed when oils are treated with hydrogen in the presence of a palladium or nickel catalyst. Because... View Article

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