Test: Study of Compounds - Hydrogen Chloride - Class 10 MCQ

The boiling point of Hydrogen Chloride is -83°C. This low boiling point is indicative of its gaseous state under standard conditions and its volatility.

Aqua regia is formed by mixing one part concentrated nitric acid with three parts concentrated hydrochloric acid. This mixture is known for its ability to dissolve noble metals like gold and platinum.

The molecular formula of Hydrogen Chloride is HCl, which indicates it consists of one hydrogen atom and one chlorine atom. This simple structure is fundamental to its chemical properties and reactions.

The nascent chlorine produced in aqua regia is highly reactive and can dissolve noble metals such as gold and platinum, forming their soluble chlorides. This property makes aqua regia an important solution in metallurgical applications.

Hydrochloric acid is corrosive and can cause blisters on the skin upon contact. This property is important to consider when handling the acid in laboratory or industrial settings.

Hydrochloric acid reacts with carbonates to produce water and carbon dioxide. This reaction is evidenced in the reaction of HCl with sodium carbonate, resulting in effervescence from the released CO2 gas.

Hydrochloric acid is primarily used in the manufacture of dyes and drugs, among other applications. Its versatility makes it a crucial chemical in various industrial processes.

The density of hydrochloric acid is 1.2 gm/cc. This relatively high density contributes to its behavior and interactions in various chemical applications.

The reaction of hydrochloric acid with zinc produces hydrogen gas as one of the products. This reaction is commonly used to demonstrate the activity of metals with acids.

Copper does not react with hydrochloric acid because it is less reactive than hydrogen in the electrochemical series. This illustrates the importance of metal reactivity in acid-base chemistry.

d) It is 1.28 times heavier than air.

Why are the others false:

a) Lighter than air — false; HCl (36.5 g/mol) is heavier than air (~29 g/mol).
b) Highly insoluble — false; HCl is very soluble in water.
c) Can be collected over water — false; it dissolves readily in water.

Hydrochloric acid is classified as monobasic, meaning it dissociates in aqueous solution to produce one hydrogen ion (H+) per molecule. This property contributes to its acidic nature.

When Hydrogen Chloride gas is heated above 500°C, it dissociates into hydrogen (H2) and chlorine (Cl2) gas. This thermal dissociation is a critical reaction in various chemical processes.

Hydrogen Chloride gas is prepared by heating sodium chloride (NaCl) with concentrated sulfuric acid (H2SO4). This reaction produces HCl gas and is a common laboratory method for generating this compound.

Hydrochloric acid is acidic in aqueous solution because it dissociates to produce hydrogen ions (H+), which are responsible for its acidic properties and behavior.

Hydrogen Chloride has a covalent bond, formed by the sharing of electrons between the hydrogen and chlorine atoms. This type of bond is characteristic of molecular compounds.

When hydrochloric acid is combined with ammonia, it results in the formation of dense white fumes of ammonium chloride (NH4Cl). This is a classic demonstration of acid-base reactions.

The reaction Ca + 2HCl → CaCl2 + H2 illustrates hydrochloric acid reacting with a metal (calcium) to produce a metal chloride and hydrogen gas. This showcases the typical reactivity of acids with metals.

The freezing point of hydrochloric acid is -113°C, which means it remains in a liquid state at much lower temperatures compared to many other substances.

The reaction MgO + 2HCl → MgCl2 + H2O shows hydrochloric acid reacting with an oxide (magnesium oxide), resulting in the formation of a salt (magnesium chloride) and water.