The carbon-hydrogen bond (C-H bond) is a bond between carbon and hydrogen atoms that can be found in many organic compounds. Compound classes consisting solely of C-H bonds and C-C bonds are alkanes, alkenes, alkynes, and aromatic hydrocarbons. Collectively they are known as hydrocarbons.

Correct Option: A

The carbon-hydrogen bond (C-H bond) is a bond between carbon and hydrogen atoms that can be found in many organic compounds. Compound classes consisting solely of C-H bonds and C-C bonds are alkanes, alkenes, alkynes, and aromatic hydrocarbons. Collectively they are known as hydrocarbons.

Heliox is a breathing gas composed of a mixture of helium (He) and oxygen (O2). Heliox has been used medically since the 1930s, and although the medical community adopted it initially to alleviate symptoms of upper airway obstruction, its range of medical uses has since expanded greatly, mostly because of the low density of the gas

Correct Option: A

Heliox is a breathing gas composed of a mixture of helium (He) and oxygen (O2). Heliox has been used medically since the 1930s, and although the medical community adopted it initially to alleviate symptoms of upper airway obstruction, its range of medical uses has since expanded greatly, mostly because of the low density of the gas

Carbon monoxide (CO) is a colourless, odorless, non-irritating but very poisonous gas which is a product by incomplete combustion of fuel such as natural gas, coal or wood. Vehicular exhaust is a major source of carbon monoxide.

Correct Option: B

Carbon monoxide (CO) is a colourless, odorless, non-irritating but very poisonous gas which is a product by incomplete combustion of fuel such as natural gas, coal or wood. Vehicular exhaust is a major source of carbon monoxide.

Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols – for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.

Correct Option: C

Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols – for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.

Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.

Correct Option: C

Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.