Dry ice, sometimes referred to as “cardice,” is the solid form of carbon dioxide. It is used primarily as a cooling agent. Its advantages include lower temperature than that of water ice and not leaving any residue. It is useful for preserving frozen foods, ice cream, etc., where mechanical cooling is unavailable.

Correct Option: B

Dry ice, sometimes referred to as “cardice,” is the solid form of carbon dioxide. It is used primarily as a cooling agent. Its advantages include lower temperature than that of water ice and not leaving any residue. It is useful for preserving frozen foods, ice cream, etc., where mechanical cooling is unavailable.

Dolomite is a common rock-forming mineral. It is a calcium magnesium carbonate with a chemical composition of CaMg(CO₃)₂. It is the primary component of the sedimentary rock known as dolostone and the metamorphic rock known as dolomitic marble. Dolomite is used in the Pidgeon process for the production of magnesium.

Correct Option: C

Dolomite is a common rock-forming mineral. It is a calcium magnesium carbonate with a chemical composition of CaMg(CO₃)₂. It is the primary component of the sedimentary rock known as dolostone and the metamorphic rock known as dolomitic marble. Dolomite is used in the Pidgeon process for the production of magnesium.

Sodium bicarbonate and organic acid (Formic acid, Acetic acid, Carbonic acid, etc) react vigorously to liberate carbon dioxide. For example, Sodium bicarbonate (NaHCO₃) when treated with acetic acid reacts vigorously to liberate carbon dioxide.
NaHCO_{3 + CH3COOH → CH3COONa + H2O + CO2}

Correct Option: D

Sodium bicarbonate and organic acid (Formic acid, Acetic acid, Carbonic acid, etc) react vigorously to liberate carbon dioxide. For example, Sodium bicarbonate (NaHCO₃) when treated with acetic acid reacts vigorously to liberate carbon dioxide.
NaHCO_{3 + CH3COOH → CH3COONa + H2O + CO2}

The oxide of Sulphur (Sulphur Dioxide) is washed down on earth as acid rain. It makes the soil acidic by lowering its pH; this affects plants and animals adversely. Acid rain contains H⁺, SO₄^2- ions which when added to the soil leaches the nutrients from the soil. Acid rain renders the river or even ocean water acidic, thereby affecting marine animals adversely. Changes in pH of fresh water affect the reproduction and survival or many species or fish.

Correct Option: C

The oxide of Sulphur (Sulphur Dioxide) is washed down on earth as acid rain. It makes the soil acidic by lowering its pH; this affects plants and animals adversely. Acid rain contains H⁺, SO₄^2- ions which when added to the soil leaches the nutrients from the soil. Acid rain renders the river or even ocean water acidic, thereby affecting marine animals adversely. Changes in pH of fresh water affect the reproduction and survival or many species or fish.

The chemical composition of Heavy water (deuterium oxide) is 2H₂O or D₂O. It is a form of water that contains a larger than normal amount of the hydrogen isotope deuterium (2H or D, also known as heavy hydrogen), rather than the common hydrogen-1 isotope (1H or H, also called protium) that makes up most of the hydrogen in regular water.

Correct Option: D

The chemical composition of Heavy water (deuterium oxide) is 2H₂O or D₂O. It is a form of water that contains a larger than normal amount of the hydrogen isotope deuterium (2H or D, also known as heavy hydrogen), rather than the common hydrogen-1 isotope (1H or H, also called protium) that makes up most of the hydrogen in regular water.