Chemistry - Study Mode
[#916] The aprotic solvent is
Correct Answer
(B) C 6 H 6
Explanation
Solution: In chemistry, aprotic solvents are solvents that cannot donate hydrogen bonds (protons). They lack an acidic hydrogen atom and thus do not participate in hydrogen bonding. Aprotic solvents are often used in reactions where proton transfer is not desired. Among the options provided: H 2 O (Option A) is a protic solvent as it can donate hydrogen bonds. HF (Option C) is also a protic solvent as it contains hydrogen atoms bonded to fluorine, which can participate in hydrogen bonding. NH 3 (Option D) is a protic solvent as it can donate a hydrogen atom in solution. However, C 6 H 6 (Option B) , which is benzene, is an example of an aprotic solvent . It lacks hydrogen atoms that are capable of forming hydrogen bonds. Therefore, Option B: C 6 H 6 is the correct choice for an aprotic solvent.
[#917] Which of the following has the highest lattice energy?
Correct Answer
(C) NaF
Explanation
Solution: For compounds containing ions of same charge, lattice energy increases as the size of ions decreases. Thus, NaF has highest lattice energy.
[#918] Which of the following substance is highly plastic ?
Correct Answer
(D) Clay
Explanation
Solution: Clays exhibit plasticity when mixed with water in certain proportions. When dry, clay becomes firm and when fired in a kiln, permanent physical and chemical changes occur. These reactions, among other changes, cause the clay to be converted into a ceramic material. Because of these properties, clay is used for making pottery items, both utilitarian and decorative. Different types of clay, when used with different minerals and firing conditions, are used to produce earthenware, stoneware, and porcelain. Prehistoric humans discovered the useful properties of clay. Some of the earliest pottery shards recovered are from central Honshu, Japan. Clay tablets were used as the first known writing medium, inscribed with cuneiform script through the use of a blunt reed called a stylus. Purpose-made clay balls were also used as sling ammunition.
[#919] Soldering of two metals is possible because of the property of :
Correct Answer
(C) Cohesion
Explanation
Solution: Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting throughout the interior of substance. Soldering leads to alloy formation at the layer between two metals.
[#920] The oil used in the froth floatation process is
Correct Answer
(D) pine oil
Explanation
Solution: The oil used in froth flotation process in pine oil, it is because it does not have affinity towards water and it easily attracts impurities and impurities can easily wash away.