Explanation

The freezing point of heavy water is 3.82°C:

| | Heavy water (D2O) | Regular water |

|---|---|---|

| Freezing point | 3.82°C | 0°C |

| Boiling point | 101.42°C | 100°C | 

Heavy water is made up of two deuterium atoms and one oxygen atom.

It contains more deuterium, a hydrogen isotope, than regular water, which contains hydrogen-1.

Heavy water is used in reaction mechanisms.

It is is prepared by electrolyzing water.

Explanation

The cell constant is a measure used in conductivity measurements and is defined as the ratio of the distance between the electrodes to the area of the electrodes.

Its unit is cm⁻¹ (inverse centimeters), which reflects the geometric configuration of the cell used in measuring conductivity.

Explanation

DNA (deoxyribonucleic acid) is a biopolymer composed of long chains of nucleotides, which are the building blocks of genetic material.

Biopolymers are naturally occurring polymers produced by living organisms.

Explanation

O₂ (oxygen molecule) is paramagnetic because it has unpaired electrons in its molecular orbitals.

According to Molecular Orbital Theory (MOT), the electronic configuration of O₂ reveals 

There are two unpaired electrons in the π* anti-bonding orbitals, which are responsible for its paramagnetic properties.

Hybridization and resonance do not directly explain the presence of unpaired electrons in this context.

Explanation

In the complex  [Ni(CN) 4] ^2−, nickel is in the +2 oxidation state and is surrounded by four cyanide (CN⁻) ligands.

According to Crystal Field Theory and based on the strong field nature of cyanide ligands, the complex adopts a square planar geometry.

Explanation

Alpha rays, or alpha particles, are the least penetrating form of radiation.

They consist of two protons and two neutrons

Making them relatively large and heavy compared to beta and gamma rays.

Explanation

When an acid reacts with a carbonate, it produces salt, water, and carbon dioxide as products.

A general reaction is:

Acid + Carbonate → Salt + Water + CO₂

Example: HCl + CaCO₃ → CaCl₂ + H₂O + CO₂

Explanation

Iron is essential in making hemoglobin, a protein in red blood cells.

These red blood cells help carry oxygen throughout your body.

Explanation

Burning pure hydrogen produces only water vapor as a byproduct, causing no harmful pollution like carbon or sulfur oxides.

Hence, hydrogen is considered a clean fuel with no emission of pollutants such as sulphur dioxide or carbon dioxide.

Explanation

Nylon actually has excellent abrasion resistance, not poor.

It is also highly resilient, resistant to insects, fungi, and many chemicals.