Explanation

Mass number = Protons + Neutrons in an atom.

Carbon's most common isotope (Carbon-12) has 6 protons and 6 neutrons, making its mass number 12.

Explanation

Metals make up the majority of elements in the periodic table, especially on the left and center.

They are generally good conductors, malleable, ductile, and have high melting points.

Explanation

An atom is the smallest unit of matter that retains the properties of an element.

It consists of subatomic particles like electrons, protons, and neutrons.

Explanation

During lightning or electrical discharges, nitrogen (N₂) reacts with oxygen (O₂) to form nitric oxide (NO).

This is the first step in the natural nitrogen cycle involving atmospheric fixation.

Explanation

Hydrochloric acid (HCl): is a strong inorganic acid, also known as a mineral acid.

Citric acid, acetic acid, and lactic acid are organic acids found in citrus fruits, vinegar, and muscle tissue, respectively.

Explanation

 Paper chromatography works on the principle of adsorption and partition,

Where compounds are separated based on their movement through paper (stationary phase) with the help of a solvent (mobile phase).

Explanation

James Simpson, a Scottish doctor, is credited with discovering the anesthetic properties of chloroform in 1847

Explanation

Dolomite is a carbonate mineral composed of CaMg(CO₃)₂.

It contains both calcium and magnesium carbonates, making it a double carbonate salt.

Explanation

Greenhouse Effect refers to the process where certain gases, like carbon dioxide and methane, trap heat from the sun in the Earth's atmosphere, leading to an increase in temperature.

It is a natural process, but human activities have intensified it, contributing to global warming.

Explanation

An anion is a negatively charged ion.

H⁻ (hydride ion) carries a negative charge, so it is an anion.