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The enthalpy change of neutralisation involving weak acids are smaller in magnitude compared to that between strong acids and strong bases. This is because weak acids/bases are partially dissociated, which means not all hydrogen ions are free to react with hydroxide ions. For strong acids and bases, the enthalpy of neutralisation values are always closely similar with the values -57 and -58 KJ/mol. We know that strong acids completely ionize in water. In case of weak acids, only partial dissociation of its ions occurs.

An endothermic reaction is any chemical reaction that absorbs heat from its environment.

NaH is a saline (salt-like) hydride, composed of Na+ and H− ions. NaH (sodium hydride) is considered an ionic compound because it is composed of a metal (sodium) and a non-metal (hydrogen), where sodium readily loses an electron to form a positive ion (Na+) and hydrogen gains an electron to form a negative ion (H-) creating an ionic bond between them.

The oxides which neither react with acids nor react with bases are known as neutral oxides. Carbon monoxide neither reacts with acids nor reacts with bases. Thus, carbon monoxide is a neutral oxide, produced when combustion reactions are not fully completed, either through lack of oxygen or due to low mixing

Chlorine is a yellow-green gas at room temperature. Chlorine has a pungent, irritating odor similar to bleach that is detectable at low concentrations. Exposure to low concentrations of chlorine (1 to 10 ppm) may cause eye and nasal irritation, sore throat, and coughing. Inhalation of higher concentrations of chlorine gas (>15 ppm) can rapidly lead to respiratory distress with airway constriction and accumulation of fluid in the lungs (pulmonary edema).

In the majority of power plants, sulfur appears due to coal burning which is used to generate electricity.

There are 4 bond pairs in CO₂ and no lone pairs are there.

During the Contact Process for manufacturing sulfuric acid, sulfur dioxide has to be converted into sulfur trioxide, which is done by passing sulfur dioxide and oxygen over a solid vanadium(V) oxide catalyst.

ZnS (Zinc Sulfide) screen was used because it emits a flash of light when struck by an alpha particle. This is a phenomenon called Radio luminescence in which a flash of light is observed on the screen when acted upon by a radioactive substance.

Iron reacts with steam to form iron oxide and hydrogen gas.

-Zn is a reducing agent, HCl is an oxidizing agent. -the zinc is oxidized

Cast iron + haematite = wrought iron

Pre-heated air at about 600ºC is blown into the furnaces from the bottom through the tuyeres.

Carboxylic acids and enols react with sodium bicarbonate to liberate carbon dioxide. E,g CH\(_3\)COOH

An alkene is produced when dehydration of alcohol is performed. Alcohol dehydration is an example of an elimination reaction which is quite the opposite of substitution reaction and addition reaction. The products of the dehydration of a primary alkanol are water and an alk-1-ene (1-alkene). Butanol gives a mixture of but-1-ene and but-2-ene when dehydrated.