All Free Chemistry MCQs with Answers

• A. Presence of hydrogen at ∞-carbon
• B. Condensation reaction
• C. Presence of carboxylic group
• D. Hydrogen bonding

Explanation: The oxygen atom carbonyl group of one carboxylic acid forms hydrogen bond with hydrogen atom of hydroxyl group of other carboxylic acid.

• A. H-atom of R group
• B. Carbonyl group
• C. H-atom of OH group
• D. Carboxylic group

Explanation: Reaction with carboxylic acid and carbonates are example of E-substituition. Na+CH3COOH→ CH3COONa+1/2 H2 , So, O-H bond break

• A. Electrophilic substitution
• B. Nucleophilic addition
• C. Nucleophilic substitution
• D. Oxidation

Explanation: Esterification is an example of a Nucleophilic substitution reaction. During the mechanism when alcohol attacks through lone pair of…

• A. CH3COOH, HCI
• B. CH3COOH, PCI5
• C. CH3COOH, SOCI2
• D. Both "B" and "C"

Explanation: The addition of a nucleophile to the carboxyl group is always followed by the displacement of the OH group by some other group, producing…

• A. Reaction of CH3COOH with Na
• B. Reaction of CH3COOH with NaHCO3
• C. Reaction of CH3COOH with Na2 CO3
• D. Reaction of CH3COOH with PCI5

Explanation: CH3,COOH+PCI5 → CH3-CO-CI+ POCI3+HCI, In this reaction C-O bond of carboxy

• A. OH-
• B. RCCO-
• C. -OR
• D. PhO-

Explanation: Option Ais correct.Hydroxide ion is the conjugate base of water (H2O).Water is a weak acid (in pure form) with a pKa of about 15.7.

• A. Option A
• B. Option B
• C. Option C
• D. Option D

Explanation: This is correct option as it contains functional group of carboxylic acids.

• A. methyl formate
• B. methyl acetate
• C. ethyl acetate
• D. ethyl formate

Explanation: Option D is the correct answer. Ethyl formate is an ester with the formula HCOOCH2CH3.When hydrolyzed, it produces ethyl alcohol…

• A. HClO
• B. HClO2
• C. HClO4
• D. HClO3

Explanation: The increasing order of acid strength HClO4,HClO3,HClO2,HClO is: HClO<HClO2<HClO3<HClO4.

• A. Alanine
• B. Glycine
• C. Aspartic acid
• D. Aniline

Explanation: Aniline is not an amino acid. It is an organic compound consisting of a benzene ring with an amino group (-NH2) attached to it.

• A. CnHnCOOH
• B. CnH2n+1COOH
• C. CnH2nCOOH
• D. CnH2n-2COOH

Explanation: CnH2n+1COOH, is the correct general formula for monocarboxylic acids. This formula represents a carboxylic acid where there is a carbon…

• A. Formic acid
• B. Oxalic acid
• C. Carbonic acid
• D. Acetic acid

Explanation: Acetic acid is correct. Acetic acid, also known as ethanoic acid, is used in the manufacture of synthetic fibers, particularly in the…

• A. She said they had texted each other earlier in the day to say they loved each other.
• B. She said they had texted one the other earlier in the day to say they loved each other.
• C. She said they had texted each other earlier in the day to say they loved ourselves.
• D. She said they had texted each other earlier in the day to say they loved each the other.

Explanation: "Each other" is used correctly to indicate reciprocal action between the two parties involved.

• A. Unfortunately, I had only a little friends those days, and they did not help me.
• B. Unfortunately, I had only few friends those days, and they did not help me.
• C. Unfortunately, I had only the few friends those days, and they did not help me.
• D. Unfortunately, I had only a few friends those days, and they did not help me.

Explanation: The sentence is structured correctly, using the indefinite article "a" before "few" to indicate a small, indefinite number.

• A. released when a bond is formed between two gaseous atoms, or equally the energy needed to break it
• B. needed to melt an ionic solid
• C. stored in the nucleus
• D. needed to ionise an atom

Explanation: Breaking a bond is endothermic and forming the same bond is exothermic by exactly the same amount, so bond energy can be quoted either way…

• A. Bond order 3 and Isoelectronic
• B. Bond order three and weak field ligands
• C. Bond order two and π acceptors
• D. Isoelectronic and weak field ligands

Explanation: Each of these have same number of electrons;Number of electrons in CO = 6+8 = 14Number of electrons in CN- = 6+7+1 = 14Number of electrons…

• A. I<Br< F<Cl
• B. I<Cl<F<Br
• C. I<F<Br<Cl
• D. F<Cl<Br<I

Explanation: Electron affinity is defined as the change in energy of a neutral atom when an electron is added to the atom to form a negative ion.

• A. Polar, Nonpolar
• B. Nonpolar, Neutral
• C. Polar, Neutral
• D. Neutral, Nonpolar

Explanation: CCl4, or carbon tetrachloride, contains only polar bonds. The molecule, however, is nonpolar because it has symmetrical geometry.

• A. Decreases
• B. Increases
• C. Remains same
• D. No change

Explanation: Option C is correct since the number of shells remains the same across a period.

• A. Electron affinity
• B. Ionization energy
• C. Electronegativity
• D. None of these options is correct

Explanation: A sufficient gap between the 1st and 2nd ionization energy indicates that the valency is 1.