Acid, Base and Salts RRB PYQ

Bleaching powder, chemically known as calcium hypochlorite (Ca(OCl)2), acts as an oxidizing agent. This means it can accept electrons from other substances during a chemical reaction. Bleaching powder releases chlorine, which is a strong oxidizer, making it effective in bleaching and disinfecting applications. It is widely used for disinfecting water, bleaching fabrics, and as a sanitizing agent.

When diluting a concentrated acid with water, heat is gradually released and readily absorbed by the larger volume of water. Conversely, when water is added to concentrated acid, a significant amount of heat is rapidly generated. This sudden heat production can cause some of the water to turn into steam explosively, potentially splashing the acid onto skin or clothing and causing acid burns. Additionally, the excessive heating may lead to the glass container breaking.

Litmus is a dye extracted from lichens, which are symbiotic organisms consisting of fungi and algae or cyanobacteria. Litmus is commonly used as a pH indicator, turning red in acidic conditions and blue in alkaline conditions.

Acid rain has a pH value of less than 5.6, which is more acidic than normal rainwater. Normal rainwater has a pH of around 5.6 due to the natural presence of carbon dioxide, which forms weak carbonic acid. Acid rain is primarily caused by the emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) from industrial activities and vehicles. When these pollutants mix with water vapor in the atmosphere, they form stronger acids such as sulfuric acid (H2SO4) and nitric acid (HNO3).

The correct and safe way to make a solution of acid in water is to add acid to water, not the other way around. This is because adding water to concentrated acid can cause an exothermic reaction, which releases a large amount of heat very quickly. By adding acid to water, the heat generated is absorbed more gradually by the larger volume of water, making the process much safer.

The chemical name of quicklime is calcium oxide (CaO). It's a white, caustic, alkaline solid often produced by roasting calcium carbonate to drive off carbon dioxide. Quicklime plays a crucial role in various applications, including cement production and water treatment.

Hydrolysis is a reaction where a substance reacts with water, breaking down the molecule. Electrolysis uses electricity to drive a non-spontaneous chemical reaction. Neutralisation is the specific reaction between an acid and a base, where they cancel out each other's properties to form a salt and water. Distillation is a separation technique used to purify liquids by boiling and condensing the vapors.

The pH scale ranges from 0 to 14 and is used to measure the acidity or basicity of a solution. A pH value of 7 is considered neutral, meaning the concentration of hydrogen ions (H+) is equal to the concentration of hydroxide ions (OH-). Solutions with a pH less than 7 are acidic, while those with a pH greater than 7 are basic or alkaline.

The pH value is a measure of the hydrogen ion concentration in a solution. As the concentration of hydronium ions (H3O+) increases, the pH value decreases. A lower pH value indicates a higher acidity of the solution. The pH scale ranges from 0 to 14, with 7 being neutral, below 7 acidic, and above 7 basic.

Limestone, chalk, and marble are all different forms of calcium carbonate (CaCO3). These materials have the same chemical composition but differ in their crystalline structure and formation process. Limestone is a sedimentary rock formed from the accumulation of calcium carbonate shells and skeletons of marine organisms. Chalk is a soft, white, porous rock made up of the microscopic remains of marine plankton.