BOARD OF INTERMEDIATE EDUCATION
TELANGANA
BASIC LEARNING MATERIAL
CHEMISTRY - I
(ENGLISH MEDIUM)
District Collector & Magistrate Nodal Officer
Sri. Rajarshi Sha, I.A.S., Sri. K. Sathyanarayana
Medak District. Medak District.
Under the guidance of : COMPILED BY:
Sri. K. Shashidhar, (Principal, GJC Narsingi) Sri. B. Venkatesham, JL in Chemistry (GJC Boys Medak)
Sri. P. Avaneesh Reddy, (Principal, GJC Shankarampet – A) Sri. K. Surender Reddy, JL in Chemistry, (GJC Kowdipally)
Sri. T. Srinivas Goud, (Principal, GJC Boys, Medak) Sri. K. Naveen Kumar, JL in Chemistry (GJC Kulcharam)
Smt. M. Sridevi, (Principal, M.S., JC, Shankarampet – R) Sri. V. Aravind Kumar, JL in Chemistry, (TSMS JC, Ramayampet)
Sri. V. Machendranath, (Principal, Sri. S. Nagaraju, JL in Chemistry, (Geetha Jr.College, Medak)
Siddarth / Adarsha Jr. College, Medak.)
1
, CHEMISTRY - I
Very Short Answers (2 Marks)
1. State Graham’s Law of diffusion?
Ans: Graham’s Law of diffusion: The rate of diffusion (r) of a gas is inversely propositional
to the square root of its density (d)” at constant temperature and pressure.
r 1/ d
2. State Dalton’s law of partial pressures?
Asn: The total pressure entered by a mixture of chemically non – reacting gases at a given
temperature and volume is equal to the sum of partial pressures of the component gases.
P = P1 + P2 + P3 ......
3. Which gas diffuses faster among N2, O2, CH4 gases? Why?
Ans: The molecules weights of the given gases are N2 (28), O2 (32) and CH4 (16). The
lighter gases diffuse faster than heavier gases. Hence, CH4 diffuses faster.
4. What is Bolzman’s constant? Give its value?
Ans: Boltzman’s constant is the gas constant per molecule
Boltzman’s Constant K = R/N
= 1.38 x 10-16 erg / K. Molecule
5. How many times methane diffuses faster than sulphur dioxide?
Ans: According to graham’s Law of diffusion
Hence methane gas diffuses 2 times faster than SO2.
6. What are Isobars?
Ans: The curves (or) graphs that can be drawn at constant pressure are called Isobars.
Ex: Graph drawn between Volume and Temperature.
7. Why pressure cooker is used for cooking food in hills?
Ans: At hill areas pressure cooker is used for cooking food because low atmospheric
pressure is observed at high altitudes. At high altitudes liquids boil at low temperature.
8. Give the ratio of RMS average and most probable speeds of gas molecules?
9. How many numbers of moles of glucose are present in 540 Grams of Glucose?
Ans: G.M. Weight of (C6H12O6) Glucose = 180.
No. Of Moles = Weight / G.M Weight = 540/180 = 3
10. The empirical formula of a compound is CH2O. Its molecular weight is 90.
Calculate the molecular formula of the compound.
Ans: Molecular formula = n (Empirical formula)
N =- Moleculas weight / Empirical weight = 90 /30 = 3
Mol. Weight = 90
Empirical weight (CH2O) = 30.
Moleculas formula = 3 (CH2O) = C3H6O3.
2
, 11. What is Redox concept? Give an example?
Ans: Redox reactions are the reactions in which reduction and oxidation both takes place
12. Calculate the weight of 0.1 mole of Sodium carbonate?
Ans: No. of moles = weight / G.Mol. Wt.
No. of Moles = 0.1
G.M.W of Na2CO3 = 106
Weight = 106 x 0.1 = 10.6 Gr.
13. State the first law of the thermodynamics?
Ans: Energy can neither be created nor destroyed, but it can be transformed from one
form to another”.
14. State third law of thermodynamics?
Ans: The entropy of a pure crystalline substance is Zero at the absolute Zero of a
temperature (-2730C)
15. What are intensive and extensive properties?
Ans: Intensive properties : The properties which do not depend upon the quantity of
matter are called intensive properties.
Ex: Pressure
Extensive Properties : The properties which depend upon the quantity of matter are called
extensive properties
Ex: Mass.
16. Write the relation between Kp and Kc
Ans: Kp = Kc (RT) Δn
Δn = No. of gaseous products – No. Of gaseous reactants
17. Give two chemical equilibrium reactions for which Kp > Kc.
Ans: 1. 2NH3 (g) N2 (g) + 3H2 (g)
Δn = nP – nR = (3+1) – 2 = 2
Δn = 2 (+ve)
Therefore Kp > Kc
2. 2 SO3 (g) 2 SO2 (g) + O2 (g)
Δn = nP – nR = (2+1) – 2 = 1
Δn = 1 (+ve)
Therefore Kp > Kc
18. What is Lewis acid? Give one example?
Ans: A substance which can accept an electron pair to form a co-ordinate covalent bond
with donor is called Lewis Acid.
Ex: BF3.
19. What is meant by Ionic product of water?
Ans: At a given temperature the product of the concentrations of H+ and OH- ions in water
is called ionic product of water
Kw = [H+] [OH-]
At 250 C KW = 1.008 x 10-14 mole2 / Lit 2.
3
TELANGANA
BASIC LEARNING MATERIAL
CHEMISTRY - I
(ENGLISH MEDIUM)
District Collector & Magistrate Nodal Officer
Sri. Rajarshi Sha, I.A.S., Sri. K. Sathyanarayana
Medak District. Medak District.
Under the guidance of : COMPILED BY:
Sri. K. Shashidhar, (Principal, GJC Narsingi) Sri. B. Venkatesham, JL in Chemistry (GJC Boys Medak)
Sri. P. Avaneesh Reddy, (Principal, GJC Shankarampet – A) Sri. K. Surender Reddy, JL in Chemistry, (GJC Kowdipally)
Sri. T. Srinivas Goud, (Principal, GJC Boys, Medak) Sri. K. Naveen Kumar, JL in Chemistry (GJC Kulcharam)
Smt. M. Sridevi, (Principal, M.S., JC, Shankarampet – R) Sri. V. Aravind Kumar, JL in Chemistry, (TSMS JC, Ramayampet)
Sri. V. Machendranath, (Principal, Sri. S. Nagaraju, JL in Chemistry, (Geetha Jr.College, Medak)
Siddarth / Adarsha Jr. College, Medak.)
1
, CHEMISTRY - I
Very Short Answers (2 Marks)
1. State Graham’s Law of diffusion?
Ans: Graham’s Law of diffusion: The rate of diffusion (r) of a gas is inversely propositional
to the square root of its density (d)” at constant temperature and pressure.
r 1/ d
2. State Dalton’s law of partial pressures?
Asn: The total pressure entered by a mixture of chemically non – reacting gases at a given
temperature and volume is equal to the sum of partial pressures of the component gases.
P = P1 + P2 + P3 ......
3. Which gas diffuses faster among N2, O2, CH4 gases? Why?
Ans: The molecules weights of the given gases are N2 (28), O2 (32) and CH4 (16). The
lighter gases diffuse faster than heavier gases. Hence, CH4 diffuses faster.
4. What is Bolzman’s constant? Give its value?
Ans: Boltzman’s constant is the gas constant per molecule
Boltzman’s Constant K = R/N
= 1.38 x 10-16 erg / K. Molecule
5. How many times methane diffuses faster than sulphur dioxide?
Ans: According to graham’s Law of diffusion
Hence methane gas diffuses 2 times faster than SO2.
6. What are Isobars?
Ans: The curves (or) graphs that can be drawn at constant pressure are called Isobars.
Ex: Graph drawn between Volume and Temperature.
7. Why pressure cooker is used for cooking food in hills?
Ans: At hill areas pressure cooker is used for cooking food because low atmospheric
pressure is observed at high altitudes. At high altitudes liquids boil at low temperature.
8. Give the ratio of RMS average and most probable speeds of gas molecules?
9. How many numbers of moles of glucose are present in 540 Grams of Glucose?
Ans: G.M. Weight of (C6H12O6) Glucose = 180.
No. Of Moles = Weight / G.M Weight = 540/180 = 3
10. The empirical formula of a compound is CH2O. Its molecular weight is 90.
Calculate the molecular formula of the compound.
Ans: Molecular formula = n (Empirical formula)
N =- Moleculas weight / Empirical weight = 90 /30 = 3
Mol. Weight = 90
Empirical weight (CH2O) = 30.
Moleculas formula = 3 (CH2O) = C3H6O3.
2
, 11. What is Redox concept? Give an example?
Ans: Redox reactions are the reactions in which reduction and oxidation both takes place
12. Calculate the weight of 0.1 mole of Sodium carbonate?
Ans: No. of moles = weight / G.Mol. Wt.
No. of Moles = 0.1
G.M.W of Na2CO3 = 106
Weight = 106 x 0.1 = 10.6 Gr.
13. State the first law of the thermodynamics?
Ans: Energy can neither be created nor destroyed, but it can be transformed from one
form to another”.
14. State third law of thermodynamics?
Ans: The entropy of a pure crystalline substance is Zero at the absolute Zero of a
temperature (-2730C)
15. What are intensive and extensive properties?
Ans: Intensive properties : The properties which do not depend upon the quantity of
matter are called intensive properties.
Ex: Pressure
Extensive Properties : The properties which depend upon the quantity of matter are called
extensive properties
Ex: Mass.
16. Write the relation between Kp and Kc
Ans: Kp = Kc (RT) Δn
Δn = No. of gaseous products – No. Of gaseous reactants
17. Give two chemical equilibrium reactions for which Kp > Kc.
Ans: 1. 2NH3 (g) N2 (g) + 3H2 (g)
Δn = nP – nR = (3+1) – 2 = 2
Δn = 2 (+ve)
Therefore Kp > Kc
2. 2 SO3 (g) 2 SO2 (g) + O2 (g)
Δn = nP – nR = (2+1) – 2 = 1
Δn = 1 (+ve)
Therefore Kp > Kc
18. What is Lewis acid? Give one example?
Ans: A substance which can accept an electron pair to form a co-ordinate covalent bond
with donor is called Lewis Acid.
Ex: BF3.
19. What is meant by Ionic product of water?
Ans: At a given temperature the product of the concentrations of H+ and OH- ions in water
is called ionic product of water
Kw = [H+] [OH-]
At 250 C KW = 1.008 x 10-14 mole2 / Lit 2.
3
