Q1. Define structural isomer and draw the isomeric structures of butane. Compare the structure of benzene and cyclohexane by drawing them.
Q2. What is the difference between combustion and oxidation? Under what condition an oxidation reaction can be called as combustion? Illustrate your answer with one example in each case.
Q3. (i) State the litmus test to distinguish between an alcohol and a carboxylic acid.
(ii) Give the equation for the reaction of a carboxylic acid with an alcohol. State the condition for the reaction and name the product formed. What is this reaction known as?
(iii) Write a reaction which is reverse of this reaction? Mention the conditions required for the reaction. Name and write the use of this reaction.
Q4. An organic compound A is widely used as a preservative in pickles and has a molecular formula C2H4O2 . This compound reacts with ethanol to form a sweet-smelling compound B.
(i) Identify the compound A
(ii) Write the chemical equation for its reaction with ethanol to form compound B.
(iii) How can we get compound A from B?
(iv) Name the process and write corresponding chemical equation.
(v) Which gas is produced when compound A reacts with washing soda? Write the chemical equation.
Q5. Why are certain compounds called hydrocarbons? Write the general formula for homologous series of alkanes, alkenes and alkynes and also draw the structure of the first member of each series. Write the name of the reaction that converts alkenes into alkanes and also write a chemical equation to show the necessary conditions for the reaction to occur.
Q6. (a)Draw the structure for the following compounds:
(ii) 2-methyl propane,
(b) Draw the electron dot structure for ethanoic acid.
Q7. List two reasons for carbon forming a large number of compounds. Name the type of bonding found in most of its compounds. Why does carbon form compounds mainly by this kind of bonding. Give reason why the carbon compounds:
(i) Generally have low melting and boiling points.
(ii) Do not conduct electricity in molten state.
Q8. Soaps and detergents are both types of salts. State the difference between the two. Write the mechanism of the cleansing action of soaps. Why do soaps not form lather (foam) with hard water? Mention any two problems that arise due to the use of detergents instead of soaps.
Q9. What are micelles? Why does it form when soap is added to water? Will a micelle be formed in other solvents such as ethanol also? State briefly how the formation of micelles help to clean the clothes having oily spots.
Q10. A compound A (C2H4O2) reacts with Na metal to form a compound ‘B’ and evolved a gas which burns with a pop sound. Compound ‘X on treatment with an alcohol ‘C’ in presence of an acid forms a Sweet smelling compound ‘D’ (C4H8O2). On addition of NaOH to ‘D’ gives back Band C. Identify C and D write the reactions involved.
Q11. A carbon compound ‘P’ on heating with excess conc. H2SO4 forms another carbon compound ‘Q’ which on the addition of hydrogen in the presence of nickel catalyst forms a saturated carbon compound ‘R’. One molecule of ‘R’ on combustion forms two molecules of carbon dioxide and three molecules of water. Identify P, Q and R and write chemical equations for the reactions involved.
Q12. Make the structure of methane by showing sharing of electrons between carbon and hydrogen atoms. How could you convert methane into chloroform by substitution reaction? Explain with the help of chemical reactions.
Q13. (a) A compound X with molecular formula, C2H4 burns with a sooty flame. It decolourises bromine water. Identify X. Will it dissolve in water or not? Will it conduct electricity in aqueous solution?
(b) An organic compound X is an essential constituent of-wine and beer, which is responsible for intoxication caused by these drinks. Oxidation of X yields an organic acid Y, which is present in vinegar. Name the compounds X and Y.
Q14. (a) An element of group 14 has two common allotropes, A and 8. A is very hard and is bad conductor of electricity while 8 is soft to touch and good conductor of electricity. Identify the element and its allotropes. Explain reasons for their different properties.
(b) How can we distinguish ethanoic acid and ethanol using their chemical properties? Write any three differences.
Q15. How are the following pairs related?
(i) 2, 2-dimethylpropane and 2-methylbutane
(ii) Ethane and propane
(iii) C2H5Cl and C3H7Cl
(iv) C3H4 and C2H4
Q16 . Draw the structures of
(iv) Sodium Ethanoate
(v) Butanoic Acid
(vii) Sodium Ethoxide
(viii) Sodium Stearate
(x) Sodium Acetate
Q17. Give account of chemical properties?
(i) combustion of ethanol
(ii) oxidation of ethanol
(iii) reaction of C2H5OH with sodium metal
(iv) dehydration of C2H5OH
(v) reaction of C2H5OH with ethanoic acid
Q18. An organic compound A with molecular formula C4H8O2 on alkaline hydrolysis gives two compound B and C. C on acidification with dil. HCl gives D. Oxidation of B with K2Cr2O7/H2SO4 also gives D. Identify A, B, C and D and explain all the reactions involved.