Practice MCQ Questions and answers on Chemistry-GK

The lightest gas which is non-inflammable is helium.

The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds). Their partial hydrogenation reduces most but not all, of these carbon-carbon double bonds. Hydrogenation converts liquid vegetable oils into solid or semi-solid fats, such as those present in margarine. Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H₂) and another compound or element, usually in the presence of a catalyst. The process is commonly employed to reduce or saturate organic compounds. Hydrogenation typically constitutes the addition of pairs of hydrogen atoms to a molecule, generally an alkene.

Carbon dioxide is a pure substance, provided there is nothing else in it. A “pure substance” does not mean an element. Rather, it means that the given substance has definite physical and chemical properties. “Pure substances” can be either “Elements” or “Compounds” because all substances belonging to these categories have definite physical and chemical properties. A mixture does not have definite physical and chemical properties, and combine in varying proportions.

NCL, India is a research, development and consulting organization with a focus on chemistry and chemical engineering. It has a successful record of research partnership with industryand is located in Pune. NCL belongs to the family of Council of Scientific and Industrial Research (CSIR), the largest chain of public funded research organization in world. NCL’s human resources comprise of over 1000 people of whom 350 are scientist, 110 are technical staff with advanced degrees in science, technology or engineering. Over 400+ students pursue their doctoral research leading to Ph.D degree. Over 400+ research papers in international journals. Over 70+ Indian and foreign patents granted to NCL.

Antoine Lavoisier is known as the 'father of modern chemistry'.

Spirit is very volatile. So when it is exposed, it evaporates rapidly to the air if released into the environment, producing a cool effect.

Iodine is a sublimate.

Biogas is essentially a mixture of Methane (CH₄, around 55-75%) but also contains Carbon Dioxide (CO₂), around 25-30%), varying quantities of Water (H₂O) and Hydrogen Sulphide (H₂S). Other compounds can also be found, especially in waste dump biogas: Ammonia (NH₃), Hydrogen (H₂), Nitrogen (N₂) and Carbon Monoxide (CO). Methane is the valuable component under the aspect of using biogas fuel.

Biogas mainly comprises of three main gases. It is a mixture of methane, hydrogen, and carbon dioxide.

Sludge is a by product of sewage treatment and can be decomposed to produce biogas.