Mole | MCQs

Explanation

Only lone pairs participate in determining geometry of molecules this statement is NOT a feature of Valence Shell Electron Pair Repulsion (VSEPR) theory.

As both lone pairs and bonding pairs of electrons participate in determining the geometry of molecules.

VSEPR theory states that electron pairs (both bonding and lone pairs) repel each other, influencing the shape of the molecule.

Explanation

Hydrocarbons do not have a tendency to form hydrogen bonding.

Because they lack highly electronegative atoms like oxygen or nitrogen that are necessary for hydrogen bonds.

In contrast, carboxylic acids, ammonia, and ethyl alcohol can all engage in hydrogen bonding due to their functional groups.

Explanation

Intermolecular forces between molecules of an ideal gas are considered absent.

As ideal gases are defined by the assumption that their particles do not attract or repel each other.

This allows them to occupy space independently and move freely.

Explanation

The number of moles is directly proportional to the mass of an element.

It is calculated by dividing the mass of the element by its molar mass.

Explanation

Formaldehyde contains:

• one carbon atom
• two hydrogen atoms
• one oxygen atom.

The formaldehyde formula is written CH2O or HCHO,

At room temperature, formaldehyde is a colorless, flammable gas that is a distinct, pungent smell.

It is also known as :

• methanal,
• methylene oxide,
• oxymethylene,
• methyl aldehyde
• oxomethane.

Explanation

Dipole moment of H2 =0 ( zero ).

The ionic character exists in H2 molecule but no dipole moment or bond moment exists permanently.

In these diatomic molecules, the shared pair of electrons lies between the nucleus of the two bonded atoms.

Hence, no separation of charges occurs. I.e., these molecules have zero dipole moment.

Explanation

RNA stands for Ribonucleic acid

Explanation

DNA (Deoxyribonucleic acid) is a large molecule made up of smaller units called nucleotides. Each nucleotide is composed of:

• A sugar molecule (deoxyribose)
• A phosphate group
• One of four nitrogenous bases: Adenine (A), Guanine (G), Cytosine (C), and Thymine (T)