Chemistry is one of the physical sciences that help us to explain and describe our world. It is the study of matter, properties, how and why substances combine or separate to form other substances, and how substances interact with energy. Whatever material is existing is made up of matter — even our own bodies.
Chemistry is involved in everything we do, from growing and cooking food to cleaning our homes and bodies, etc. This article consists of some basic Questions of Chemistry which not only help in the interview, viva but also in the preparation of various examinations for an entrance.
1.Which one of the following statements is incorrect?
A.Mercury is a liquid metal.
B.Bromine is a liquid non-metal.
C.Gold occurs in nature in free state.
D.Silver and copper are found in combined state only.
Explanation: Being least reactive Gold is the only metal which occurs in Free State because it is unaffected by air, moisture and other gases present in the atmosphere and inside the earth. Silver and copper both found in free as well as in combined state. Both come next in the order of inactivity series.
2.Which one of the following is a noble metal?
Explanation: Silver, Platinum and gold are completely unaffected by air and moisture and are Noble metals. It is due to their property they are expensive.
5 ऐसे तथ्य जो आप गणितीय चिन्ह अनन्त (∞) के बारे में नहीं जानते हैं
3.Babbitt is an alloy of which one of the following principal metal?
Explanation: Babbitt is an alloy of Tin. It is fusible, soft and is used for bearings. It also contains Calcium and Antimony.
4.Which was the first organic compound to be synthesized in laboratory from non-living resources?
Explanation: Urea is present in Urine and by a German Chemist in 1928, Wohler prepared Urea by heating an inorganic compound ammonium cyanate.
NH4CNO---->CO (NH2)2 [Urea]
5.Starch Iodide paper is used to test:
B.Nitrogen dioxide only
C.A reducing agent
D.An oxidising agent
Explanation: An oxidizing agent, or oxidant, gains electrons and is reduced in a chemical reaction. Also, known as electron acceptor. Examples are halogens, potassium nitrate, and nitric acid. Starch Iodide paper is used to test an oxidising agent.
ऐसे 8 काम जो आप पृथ्वी पर कर सकते हैं लेकिन अन्तरिक्ष में नही
6.Limestone used in the extraction of iron act as :
Explanation: Limestone is added as flux. It decomposes into calcium oxide and carbon dioxide. Calcium oxide combines with sand to form Calcium Silicate known as slag which is tapped out from furnace time to time.
7.Which one of the following drug is used to treat Osteoarthritis?
Explanation: Etodolac is used to treat Osteoarthritis. It is non-steroid, mild analgesic that works by reducing concentrations of certain chemicals to modify tissues that produce inflammation, relieves swelling and stiffness.
7 चीजें जो रोबोट अब आपके लिए कर सकता हैं
8.Which one of the following does not have cubic crystal system?
Explanation: Graphite has hexagonal crystal system.
9.Which one of the following is correct about ebonite?
A.It is a hard synthetic plastic formed by polymerisation.
B.It is a compound containing one-third sulphur and one-third rubber.
C.It is an allotrope of amorphous phosphorous.
D.It is a type of plutonic rock.
Explanation: A compound containing one-third sulphur and two-thirds rubber vulcanizes to form ebonite or hard rubber.
10.Which one of the following statement regarding ester is incorrect?
A.Ester is formed by the reaction of acids and alcohols.
B.The conversion of an acid into ester is termed as esterification.
C.The reaction between an ester and an acid is termed as saponification.
D.Nitroglycerin, an important explosive, is an ester.
Explanation: Saponification is the reaction between an ester and a metallic base. When the decomposition of an ester occurs with water then ester is said to be hydrolysed.