Physical Properties of Alkynes

Q.

Give an example of a non-polar molecule?

Q.

Bond length of C - C in ethane (I) Ethene (II) Ethyne (III) and Benzene (IV) follows the order

1. I > II > III > IV

2. I > II > IV > III

3. I > IV > II > III

4. III > IV > II > I

Q.

Phenol does not decompose${\mathrm{NaHCO}}_3$to evolve ${\mathrm{CO}}_2$ but Picric acid does.

1. True
2. False

Q.

Sulphur trioxide is dissolved in sulphuric acid and not in water because :

1. The gas is highly soluble in water

2. The gas is almost insoluble in water

3. The gas does not react with water

4. The gas reacts with water vigorously

Q.

C3H4 is the formula of:

1. propyne

2. butane

3. propene

4. propane

Q.

The number of hydrogen atoms in cyclohexane are

1. 5

2. 6

3. 10

4. 12

Q.

The most volatile compound among the following is:

1. 2-methyl butane

2. Isobutane

3. 2, 2-dimethyl propane

4. n-pentane

Q.

Of the following compounds, the one having a linear structure is:

1. NH₂

2. CH₄

3. C₂H₂

4. H₂O

Q.

How is bicarbonate formed?

Q. Can an organic compound having a formula CnHn is possible.give reasons to justify your answer.

Q.

What happens when methyl iodide is warmed with sodium metal?

1. Methane is produced

2. The reaction does not happen

3. Iodine is evolved

4. Ethane is produced

Q. Why silver mirror test is only for aldehydes and Ketons?

Q. (a) Hydrogen chloride solution in water turns blue litmus red and conducts electricity, while in toluene it does not. Explain why?
(b) Correct the following statement: HCl gas is not combustible but it supports combustion.
(c) Which of the following gas gives a white precipitate when reacted with silver nitrate solution acidified with dilute nitric acid?
(i) Ammonia
(ii) Hydrogen chloride
(iii) Hydrogen sulphide
(iv) Sulphur dioxide [3 MARKS]

Q. Give two examples of halogens

Q.

8.The fruity smell is of a/an-

1. Aldehyde

2. Ketone

3. Alcohol

4. Ester

Q. Acetylene on ozonolysis gives glyoxal.

1. True
2. False

Q. Which of the following polar solvents has the highest dielectric cons†an t?:-(1) H_2O, (2) D_2O, (3) CH_3OH, (4) C_2H_5OH

Q.

can all alkenes be used to ripe fruits or only ethene can be used?

Q.

What is hydrogenation?Explain its industrial application?

Q. How many covalent bonds are present in acetylene?

1. $4$
2. $5$
3. $6$
4. $3$

Q. Are Hydrocarbons, only volatile substances?

Q. From the following organic compounds given below, choose one compound in each case which relates to the description (i) to (iv): [Ethyne, Ethanol, Acetic acid, Ethene, Methane]
i) An unsaturated hydrocarbon used for welding purposes.

1. Ethene
2. Acetic acid
3. Ethyne
4. Ethanol
5. Methane

Q. Collect information about artificial ripening of fruits by ethylene.

Q. This gas is used for welding purpose.

Q. What is the reaction between propene and Br.CCl3 in the presence of sunlight. Which radical so formed attacks first on propene and why. Give full explanation

Q. Is presence of hydrocarbon, in a Substance, is only and the main reason for substance being volatile?

Q. Assertion :Acetylene is 1-alkyne. Reason: Acetylene is unsaturated hydrocarbon with $C-C$ triple bond and two hydrogen atoms. It is a linear symmetrical molecule with both triple bonded carbon atom as terminal atoms.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
2. Both Assertion and Reason are correct, but Reason is not the correct explanation for Assertion.
3. Assertion is correct, but Reason is incorrect.
4. Both Assertion and Reason are incorrect.

Q.

1. 1, 2-Ethanediol

2. Glyoxal

3. Ethyne

4. Ethene

Q. Give balanced chemical equations for the following conversations: Calcium carbide to ethyne.

Q. Ethanol and methanol are miscible in water due to:

1. dissociation of water
2. their acidic character
3. allyl groups
4. hydrogen bonding