1.
The element which cannot be detected through Lassaigne’s test is
Correct Answer
B. Oxygen
Explanation
Lassaigne's test is used to detect the presence of elements like nitrogen, sulphur, and chlorine in an organic compound. However, oxygen cannot be detected through Lassaigne's test as it does not form any specific compound that can be identified using this test. Therefore, the correct answer is Oxygen.
2.
The element which cannot be detected through Lassaigne’s test is
Correct Answer
B. Oxygen
Explanation
Lassaigne's test is a chemical test used to detect the presence of elements such as sulphur, nitrogen, and chlorine in organic compounds. However, oxygen cannot be detected through this test because it is already present in most organic compounds and is not easily separated or detected using Lassaigne's test. Therefore, the correct answer is oxygen.
3.
The element which cannot be detected through Lassaigne’s test is
Correct Answer
B. Oxygen
Explanation
Lassaigne's test is a chemical test used to detect the presence of elements like nitrogen, sulphur, and halogens (such as chlorine) in an organic compound. However, oxygen cannot be detected through Lassaigne's test because it does not form any characteristic compound that can be detected using this test. Therefore, the correct answer is Oxygen.
4.
The ionic compound formed during the fusion of 1,2-Dichloro benzene with sodium metal is AgCN
Correct Answer
B. False
Explanation
The given statement is false. The fusion of 1,2-Dichloro benzene with sodium metal does not result in the formation of AgCN (Silver Cyanide). The correct answer is not provided, but it can be determined that the given statement is false based on the information given.
5.
Functional group present in Aniline is
Correct Answer
Amine, -NH2, Amino,amine group, primary amine
Explanation
Aniline contains an amine functional group, specifically a primary amine group (-NH2). A primary amine is characterized by the presence of a nitrogen atom bonded to two hydrogen atoms and one carbon atom. In the case of aniline, the nitrogen atom is part of an aromatic ring, making it an aromatic primary amine. The presence of this functional group is responsible for the basic properties and reactivity of aniline.
6.
Fuctional group present in above structure are
Correct Answer(s)
A. Carboxylic Acid
B. pHenolic OH
C. Carbonyl Group
Explanation
The given structure contains a carboxylic acid functional group, which is characterized by the presence of a carboxyl group (-COOH). This group consists of a carbonyl group (C=O) and a hydroxyl group (OH) attached to the same carbon atom. Additionally, the structure also contains a phenolic OH group, which is a hydroxyl group attached to a benzene ring. Lastly, there is a carbonyl group present in the structure, which is a carbon atom double bonded to an oxygen atom (C=O). Therefore, the functional groups present in the structure are carboxylic acid, phenolic OH, and carbonyl group.
7.
Above Apparatus used for determination of
Correct Answer
B. Melting point
Explanation
The above apparatus is used for the determination of the melting point. This can be inferred from the options given, where the other three options (surface tension, freezing point, and viscosity) are unrelated to the apparatus shown. The apparatus appears to be a melting point apparatus, typically used in laboratories to determine the temperature at which a substance changes from a solid to a liquid state.
8.
The Force of friction between two layers of a liquid moving past one another with different velocities is
Correct Answer
B. Viscosity
Explanation
Viscosity is the correct answer because it refers to the internal friction or resistance to flow in a fluid. When two layers of a liquid are moving past one another with different velocities, the viscosity of the liquid determines the force of friction between the layers. A higher viscosity means a higher force of friction, while a lower viscosity means a lower force of friction. Surface tension, density, and refractive index do not directly relate to the force of friction between layers of a liquid moving past one another.
9.
Which of the following express the Unit of Viscosity
Correct Answer
D. All of the above
Explanation
All of the options listed, namely dyne second Cm-1, centipoise, and Kg m-1 S-1, express the unit of viscosity. Viscosity is a measure of a fluid's resistance to flow, and it is typically measured in different units depending on the system being used. Dyne second Cm-1 is the unit used in the CGS (centimeter-gram-second) system, centipoise is a commonly used unit in the metric system, and Kg m-1 S-1 is the unit used in the SI (International System of Units) system. Therefore, all of the options provided correctly express the unit of viscosity.
10.
What is the effect of temperature on Viscosity?
Correct Answer
A. Decreases
Explanation
The effect of temperature on viscosity is that it decreases. As temperature increases, the kinetic energy of the molecules in a substance also increases. This increased kinetic energy causes the molecules to move more freely, reducing the friction between them and lowering the viscosity. Conversely, as temperature decreases, the molecules move more slowly and the friction between them increases, resulting in higher viscosity. Therefore, the viscosity of a substance is inversely proportional to temperature.
11.
The existence of strong intermolecular forces of attraction in liquids gives rise to important property known as--
Correct Answer
B. Surface tension
Explanation
The existence of strong intermolecular forces of attraction in liquids gives rise to surface tension. Surface tension is the property of the surface of a liquid that allows it to resist external forces and minimize its surface area. This is due to the cohesive forces between the molecules at the surface, which pull the molecules inward and create a "skin" or "film" on the surface. Surface tension is responsible for phenomena such as capillary action, droplet formation, and the ability of insects to walk on water.
12.
SI unit of suface tension
Correct Answer
A. Nm-1
Explanation
The SI unit of surface tension is Nm-1. Surface tension is defined as the force acting per unit length on the surface of a liquid. The unit Nm-1 represents the force in Newtons acting on a surface of 1 meter in length. This unit is commonly used to measure surface tension in scientific and engineering applications.
13.
compound
parachor value
Ethane
110.5
propane
150.8
Butane
190
from the data given above
Parachor value of CH2 group is -----------
Correct Answer
40.3
Explanation
The given data provides the Parachor values for three different compounds: ethane, propane, and butane. By comparing these values, it can be observed that as the number of carbon atoms in the compound increases, the Parachor value also increases. This indicates that the Parachor value is directly proportional to the size of the compound. Since the CH2 group is present in all three compounds, it can be inferred that the Parachor value of the CH2 group is 40.3.
14.
Following reaction take place during preparation of Lassaigne extract.
Correct Answer
A. True
Explanation
The given statement "Following reaction take place during preparation of Lassaigne extract" is true. Lassaigne extract is a solution used in organic chemistry to detect the presence of nitrogen, sulfur, and halogens in a compound. During the preparation of Lassaigne extract, reactions occur between the compound being tested and sodium metal, resulting in the formation of sodium compounds of nitrogen, sulfur, and halogens. These compounds are then extracted into water and can be further analyzed. Therefore, the statement is true.
15.
Below reaction is used in confirmation of -------- element during element detection process.
Correct Answer
A. Nitrogen
Explanation
The reaction mentioned is used in the confirmation of Nitrogen during the element detection process.
16.
What will be the colour of final compound formed in given reaction
Correct Answer
A. Orange-red
Explanation
The final compound formed in the given reaction is orange-red.