BAL BHARATI PUBLIC SCHOOL, PITAMPURA, DELHI-110034
CHAPTER: CARBON &ITS COMPOUNDS
CLASS : 10
SUBJECT: CHEMISTRY
Q1: Give reason for the formation of large number of carbon compounds.
Ans 1: There are two reasons for the existence of large number of carbon compounds:
(1) Catenation : Ability to form bonds with other carbon atoms to give straight chain ,branched
chain and ring compounds.
(2) Tetravalency : Ability of carbon to link with four other monovalent atoms.
Q2: What is homologous series ? explain with an example.
Ans 2: Series of compounds in which the same functional group substitutes for hydrogen in a carbon
chain is called a homologous series .The difference between the formulae of any two successive
members is ---CH2 .For eg: CH3OH,C2H5OH and C3H7OH.
Q3: Draw the electron dot structure for :
(a)
(b)
(c)
(d)
Ethanoic acid
Butanone
Hydrogen sulphide
Ethyl ethanoate
Ans 3: Refer to N.C.E.R.T.
Q4: Why do covalent compounds have low melting & boiling points?
Ans 4: The bonds are formed by sharing of electrons .There are no ions in such compounds . There are
weak forces of attraction between the molecules .so ,they have low melting and boiling point.
Q5: An organic compound X is an essential constituent of wine and beer . X 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 and write their structural formulae. Identify X &Y . Give the equation
involved when X &Y react with each other in the presence of sulphuric acid.
Ans 5: The compound X is Ethanol & compound Y is Ethanoic acid .
CH3COOH + C2H5OH ----------- CH3COOC2H5 +H2O CATALYST : CONC.H2SO4
Q6:How can ethanol and ethanoic acid be differentiated on the basis of chemical properties?
Ans 6: Ethanoic acid reacts with sodium hydrogencarbonate liberating carbon dioxide while ethanol
does not .
CH3COOH+ NaHCO3 ---------- CH3COONa + CO2 + H2O
Ethanol does not .
Q7: Explain the mechanism of the cleaning action of soaps.
Ans 7: Soaps are sodium salts of fatty acids.The two ends of molecules of soap behave differently. The
ionic end is hydrophilic and is oriented towards water. The other hydrocarbon end is hydrophobic and
is oriented towards dirt .A micelle formation around the oily dirt takes place .(refer N.C.E.R.T FOR
DIAGRAM).
Q8: Differentiate between soaps and detergents.
Ans8: Soaps are effective in soft water only whereas detergents are effective in hard &soft water both.
Soaps are biodegradable whereas detergents are non-biodegradable.Soaps are sodium salts of fatty
acids whereas detergents are sulphonic acid salts of fatty acids.
Q9: Define isomerism .
Ans 9: The existence of an organic compounds in more than one structure having same molecular
formula but different structural formula.
Q10: Differentiate between combustion and oxidation of organic compounds.
Ans 10: Combustion involves burning of a substa nce in the presence of oxygen .whereas oxidation
involves reaction of a substance with nascent oxygen in the presence of catalyst.
Q11: Why is oxy-acetylene flame used for welding purposes?
Ans 11: Combustion of acetylene with oxygen is an exothermic process. A lot of heat is evol ved in the
reaction which is used for welding .