Explanation

Hydrogen sulphide gas is a naturally occurring chemical.

The gas has a characteristic rotten egg odor at low concentrations.

Hydrogen sulphide gas (H 2 S) is a colorless gas

Hydrogen sulphide is produced by reacting a metal sulphide (Ferrous sulphide) with a dilute acid (Sulphuric acid).

The element responsible for the rotten egg-like smell of Hydrogen sulphide is Sulphur (S).

Explanation

Cement does typically contain a small percentage of gypsum.

Gypsum (calcium sulfate dihydrate, (CaSO4 ⋅ 2H2O) is added to cement primarily to regulate the setting time.

The percentage of gypsum in cement is usually around 2-5%.

It prevents the cement from setting too quickly by controlling the rate at which the cement hydrates and hardens. 

Explanation

The molality (m) of a solution is the moles of solute divided by the kilograms of solvent. A solution that contains 1.0mol of NaCl dissolved into 1.0kg of water is a "one-molal" solution of sodium chloride.

The symbol for molality is a lower-case m written in italics.

Explanation

To calculate the total energy consumed, you can use the following approximate energy values for macronutrients:

• Carbohydrates: 4 kcal per gram
• Proteins: 4 kcal per gram
• Fats: 9 kcal per gram

Now, let's calculate the energy from each macronutrient:

Explanation

The stake-shaped band in the infrared (IR) spectrum of the carboxylic acid group typically appears around 1710 cm⁻¹.

Explanation

Raney nickel is prepared by treating a nickel-aluminum alloy with a concentrated solution of sodium hydroxide.

This process, also known as activation, dissolves much of the aluminum, leaving behind a porous, highly active nickel catalyst. 

Explanation

• An atom is the smallest possible particle of an element that can combine to form new compounds.
• Atoms are the building blocks of matter, and they cannot be broken down into smaller particles.

Explanation

• The freezing point of water is 0°C (zero degrees Centigrade). 
• The boiling point of water is 100°C (one hundred degrees Centigrade).

Explanation

The rate equation combines the powers of the concentration of each reactant as per their order in the reaction.

 Rate = k [A][B]²

Explanation

Relative atomic mass is measured by comparing an atom's mass to 1/12th the mass of a carbon-12 atom.

Carbon-12 is the standard reference in modern atomic mass scale.