TyroCity: Chemistry Notes

Nuclear Chemistry

Chemistry 11 Notes — Sat, 12 Jul 2014 05:41:42 +0000

What are radioisotopes? State one use of such isotopes.

Boron and Silicon- Old is Gold

Chemistry 11 Notes — Sat, 12 Jul 2014 05:41:42 +0000

Write the formula of Borax and boric acid.
Give an important use of Silicon.

The meniscus for mercury in a glass tube is concave downward. Explain.

Chemistry 11 Notes — Sat, 12 Jul 2014 05:41:42 +0000

Ans: Because cohesive force between molecules of mercury is greater than the adhesive force between mercury and glass molecules.

Atomic Structure

Chemistry 11 Notes — Sat, 12 Jul 2014 05:41:42 +0000

Give the electronic configuration of copper (At. no. 29) in terms of s, p, d, f orbitals.
What is an orbital? Write the shapes of s and p orbitals.
Give the electronic configuration of silver (At. No. 47) in terms of s, p, d, f orbitals.
A scientist investing the electron structure of the element concluded that the K, L and M shells were all full and that the N shell contained four electrons. What is the atomic number of that electron?
For n=4, write all possible values of l and m.
Discuss how Bhors was able to predict the line spectra of a hydrogen atom.
Write the electronic configuration of Chromium (At. No. 24) in terms of s.p.d orbitals.
An atomic orbital has n=3, what are the possible values of l and m?
What are the values for n, l and m for 2Px orbital?
An electorn possesses the quantum numbers n=2, l=0 and m=0. What so they mean?
Write the atomic number of elements whode outermost electornic configuration are represented by (a) 3S1 (b) 3P6.
What observation did Rutherford led to conclude that the nucleus of atom is very small but heavy mass?
Why is it that electron does not jump into the nucleus?
What is meant by atomic spectrum?
Write the Lewis structure of the compound formed by two elements A and B whose atomic numbers are 12 and 17 respectively.
What are the values of Principal quantum number (n) and Azimuthal quantum number (l) for the following orbitals: (i) 3S (ii) 4P
An atom of an element has 24 electrons, what is the total number of S eletrons?
Give the values of all four quantum number of 11th electorn of Magnesium (At. No. = 12).
What observations did Rutherford make the following conclusions? a) The atomic centre is positively charged. b) Most of the space inside the atom is hollow.
Give the values of all four quantum number of outermost electron of sodium atom (Z=11).
What is Bhor’s-Bury rule?

Noble gas- Old is Gold

Chemistry 11 Notes — Sat, 12 Jul 2014 05:41:42 +0000

Why are noble gases chemically inert?
What are noble gases? Write any one use of noble gases.
The first ionization energy of noble gases is higher than that of halogens. Explain.
Give an important use of noble gases.

Define Van’t Hoff’s factor. What for it used?

Chemistry 11 Notes — Sat, 12 Jul 2014 05:41:42 +0000

Wiki- The van ‘t Hoff factor is the ratio between the actual concentration of particles produced when the substance is dissolved, and the concentration of a substance as calculated from its mass. For most non-electrolytes dissolved in water, the van’ t Hoff factor is essentially 1. For most ionic compounds dissolved in water, the van ‘t Hoff factor is equal
to the number of discrete ions in a formula unit of the substance. This is true for ideal solutions only. Sometime ion pairing occurs in solution. At a given instant a small percentage of the ions are paired and count as a single particle. Ion pairing occurs to some extent in all electrolyte solutions. This causes deviation from the van ‘t Hoff factor. The deviation for the van ‘t Hoff factor tends to be greatest where the ions have multiple charges.

i=van’t Hoff= the number of particles a formula breaks up into

C6H12O6(s) ==>C6H12O6(aq) (1 mole of particles) C6H12O6 =1

NaCl(s) ==> Na⁺(aq) + Cl^-(aq) (2 moles of particles) NaCl=2

CaCl2(s) ==> Ca²⁺(aq)+ 2Cl^-(aq) (3 moles of particles) CaCl2=3

Ozone

Chemistry 11 Notes — Sat, 12 Jul 2014 05:41:42 +0000

Write resonance structures of ozone.
How does CFC deplet Ozone layer?

Language of Chemistry

Chemistry 11 Notes — Sat, 12 Jul 2014 05:41:42 +0000

Define a chemical change and point out its two important characters.
What information can you obtain from the symbol 3919K?
How many electrons and neutrons are present in the symbol 2713Al?
Two elements A and B have outer most shell electronic configuration 3s1 and 2s2 2p4 respectively, then name the chemical formed between them.

Avogadro’s Hypothesis and Its Application

Chemistry 11 Notes — Sat, 12 Jul 2014 05:41:42 +0000

In what ways have Avogadro’s hypothesis given support to Dalton’s atomic theory?

Liquid State Question

Chemistry 11 Notes — Sat, 12 Jul 2014 05:41:42 +0000

Name the physical property behind rise of liquids in capillary tube.
Define aqueous tension. Why is it subtracted from the total pressure to determine the pressure of a dry gas?
What is evaporation? How does it differ from boiling?
Define coefficient of viscosity. How coefficient of viscosity is related with viscous force?
Why is Glycerine more viscous than water?
Why is a mercury droplet spherical?
In terms of vapour pressure, what do you mean by a boiling point of a liquid?
The meniscus for mercury in a glass tube is concave downward. Explain.
What do you understand by viscosity?
What is the efect of temperature on: (a) Surface tension (b) Viscosity (c) Vapour pressure of liquid
What do you understand by the term ‘surface tension’?
How is surface tension of a liquid originated?
Define Van’t Hoff’s factor. What for it used?
What do you mean by boiling point and evaporation?
Give reason:

a) Falling liquid drops are spherical
b) Evaporation takes place from the surface of liquid
c) It is more efficient to wash clothes in hot water than cold water.

What happens to the vapour pressure of a solvent, when non volatile solute particles are dissolved in it?
Define the term coefficient of viscosity?
Why does boiling point of liquid rise on increasing pressure?
Mention physical properties of liquid due surface tansion.

NEB Model Question for Chemistry – Class 11

Chemistry 11 Notes — Sat, 12 Jul 2014 05:41:42 +0000

NEB QUESTION MODEL OF CHEMISTRY
GRADE : 11
FOR : 2070

Exam Oriented Model Question
Time : 3 hrs

Full Marks : 75

Pass Marks : 27
Group ‘A’

Attempt any Fifteen question : 15 × 2 = 30

Q.1. State Law of reciprocal proportion.

Q.2. The oxide of an element contains 67.67 % of oxygen and V.D. of its volatile chloride is 79

Q.3. Define surface tension of Liquid.

Q.4. Write down important differences between crystalline and amorphous solid.

Q.5. What is Pauli’s exclusion principle ?

Q.6. Give the values of all four quantum numbers of 11th electron of magnesium.(At. No. 12)

Q.7. What is radioactivity ?

Q.8. Write the Lewis structure of (a) H2O2 and (b) HNO3.

Q.9. Explain why HCL has polar character though it has covalent bond.

Q.10. State Modern Periodic law.

Q.11. How would you show the following reaction is a redox reaction?
Mg + Cl2 —————> MgCl2

Q.12. State Le-Chateliers principles.

Q.13. What are the difference between nascent and molecular hydrogen ?

Q.14. name any two oxides of each of the following :
(i) amphoteric
(ii) neutral.

Q.15 What is allotropy ? Name the latest discover allotropic form of carbon.

Q.16. What is meant by acid rain ? Give one major effect of acid rain.

Q.17. Distinguish between flux and slag with one example of each.

Q.18. Can sodium be extracted by the electrolysis of aqueous solutions of sodium chloride ? If not why ?

Q.19. Define electrophile and nucleophile with an example of each.

Q.20. Give IUPAC name of the following compound.
a) CH3-CH(Br)-CH(NH2)-COOH
b) CH3-C(CH3)2-C9OH)H-CH3

Q.21. What is meant by thermal cracking and catalytic cracking ?

Q.22. Identify A and B in the following reaction and give their IUPAC name.

Group ‘B’

Attempt any five Question. 5 * 5 = 25

Q.23. Urea [(NH2)2CO] is prepared by reacting ammonia with carbon dioxide :
2NH3(g) + CO2(g) —–> (NH2)2CO(aq.) + H2O(l)
In one process, 637.2 g NH3 is treated with 1142g of CO2.
(a) Which of the following reactant is the limiting reactant ?
(b) Calculate the mass of urea formed
(c) How much excess reagent (in gram) is left at the end of the reaction ?
Q.24 State Avogadro’s law. Using the law to deduce relationship between Molecular mass and vapour density.
Q.25. State and explain Hund’s rule of maximum multiplicity.
Q.26. Specify Oxidation half, reduction half, oxidizing agent and reducing agent. Balance the following equation by ion-electron or oxidation number method :
Fe2+ + H+ + NO3– ——–> Fe⁺³ + NO + H2O
Q.27. Describe the manufacture of nitric acid by Ostwald’s process.
Q.28. Explain the laboratory preparation of carbon monoxide in laboratory What happens when CO is passed through finely divided nickel ?
Q.29. Describe the detection of foreign element (N,S,X) in organic compounds.

Group ‘C’

Attempt any two questions. : 2 × 10 = 20

Q.30. State Boyle’s law and Charles law. Derive PV=nRT. What is the density (in gram per liter) of ammonia at STP if the gas in a 1.0L bulb weights 0.672g at 25oC and 733.4 mm Hg pressure.

Q.31 Describe the manufacture of sodium carbonate by ammonia soda process. Also, mention the function of limestone in the manufacture process.

Q.32. Write down the process involved in the manufacture of caustic soda by Solvay-Kellner’s process.

Law of Chemical Equivalence

TyroCity.com — Sat, 12 Jul 2014 05:41:42 +0000

Eqv. Mass of A / Eqv. Mass of B = Mass of A / Mass of B

This relation tells that the combining mass reactants is always in the ratio of their equivalent mass. This law is also known as LAW OF CHEMICAL EQUIVALENCE.

Atomic Mass = Eqv. Mass X Valency
‘Gram Eqv.’ or ‘Eqv.’
Eqv. mass of a substance, expressed in gram is ‘one gram equivalent’ or ‘1 eqv.’

Equivalent Mass of a compound

a) Eqv. mass of acid = Molecular Mass of acid / Basicity

where Basicity of an acid is defined as no. of H+ ions displaced or OH- ions combined per molecule of the acid.

Eqv. mass of H2SO4 = 98 / 2 = 49

b) Eqv. mass of Base = Molecular Mass / Acidity

where acidity of the base is defined as the no. of H+ ions consumed or OH- ions displaced per molecule of the base.

Eg.
Eq. Mass of Ca(OH)2 = 74/2 = 37

c) Eqv. mass of Salt = Molecular Mass of Salt / Total no. of charge in basic or acid radical per molecule

Eg.
Eq. mass of Na2CO3 = 106 / 2 = 53