TyroCity: Chemistry Notes

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.

What is evaporation? How does it differ from boiling?

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

Ans: Evaporation is defined as the process of conversion of liquid into vapor from the surface of the liquid at room temperature.

Evaporation	Boiling
It takes place at any temperature.	It takes place at boiling point only.
It takes place at the surface of liquid.	It takes place at the entire volume of the liquid.
It is slow and silent process.	It fast and noisy process.

Dalton’s Atomic Theory and Laws of Stoichiometry

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

State the Law of Multiple Proportions.
State the law of Constant Proportion.
State the Law of Reciprocal Proportion.
How did the law of multiple proportions encourage Dalton to introduce atomic theory?
H and O react separately to give H2O2 and H2O respectively. What law of stoichiometry is illustrated? State the law.
Phosphorous reacts with oxygen to produce P2O3 and P2O5 respectively. Which Chemical law does the data illustrate? State the Law.
State the Law of conservation of mass. Why is this law known as Law of indestructibility of matter?
12gm of Carbon react with 32gm of oxygen to produce 44gm of Carbon dioxide. Which Chemical Law do these data illustrate? State the Law.

Hydrogen

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

Show that nascent hydrogen is powerful reducing agent than molecular hydrogen.
List all the possible istopes of hydrogen. Name the isotope which does not contain neutron.
Give a reaction which shows that water contains hydrogen.
When steam is passed through red hot coke, a mixture of two gasses is obtained. Name the gases and write the reaction involved.
What happens when zinc dust is added to an acidified solution of potassium permanganate.
Differentiate between ortho and para hydrogen.
Mention important uses of eacho of the followings: a) Heavy water b) Ozone Layer c) Hydrogen gas d) Deuterium e) Tritium f) Nascent hydrogen

Metal and Metallurgical Principles

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

Name the process for concentration of sulphide ore.
Which metals can be extracted from the following ores:

Galena, cinnabar, argentite and zinc blend

Distinguish between calcination and roasting.
What is meant by aluminothermite process?
What is meant by Slag? Why is it important in metallurgy?
Which process is applied for the concentration of sulphide ore and why?
Can Sodium be extracted by the electrolysis of aqueous solution of sodium chloride? If not, why?
Distinguish between flux and slag with examples.

Environmental Pollution- Old is Gold

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

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

Define coefficient of viscosity.

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

Ans: Coefficient of viscosity is defined as the tangential force per unit area required to maintain unit velocity gradient between the layers of liquid.

Nuclear Chemistry

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

What are radioisotopes? State one use of such isotopes.

Equivalent Mass

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

Equivalent weight of an element is 32.5. What does it mean?
Why is hydrogen displacement method not applicable to determine the equivalent mass of copper?
Define equivalent weight of an element. A divalent metal has atomic weight 24. What is its equivalent weight?
4gm of a divalent metal reacts with chlorine to produce 11.1gm of its metal chloride. Calculate the atomic mass of metal.

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.

Sulphur- Old is Gold

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

How is the moisture present in SO2 gas removed?
Acid rain forms when oxides of sulphur and nitrogen react with water. What are these oxides chemically?
Identify a viscous liquid that react with table sugar (C12H22O11) giving a charred (black) mass. Give the reaction involved.
Give two examples of reactions in which H2SO4 behaves as: (a) Strong acid (b) a dehydrating agent (c) an oxidizing agent
Explain with reason, why: (a) Conc. H2SO4 should always be added to H2O but never H2O to the acid? (b) Sugar is charred in contact with conc. H2SO4?
Write any two differences between the bleaching action of Cl2 and SO2.
What happens when H2S is passed through acidified potassium permanganate solution?
What happens when gas obtained by heating oxalic acid in presence of conc. H2SO4 is passed through heated caustic soda?
Write balanced chemical reactions for the laboratory preparation of: (a) Hydrogen Sulphide (b) Sulphurdioxide
What happens when a moist red flower is introduced into a gas jar containing SO2 gas?
Give a reaction of each to show: (a) SO2 as an oxidizing agent (b) H2S as an analytical agent

Define aqueous tension. Why is it subtracted from the total pressure to determine the pressure of a dry gas?

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

Ans: Aqueous tension is defined as the partial pressure of the water vapour present in the moist gas.
When the gas is colleced over the water, it becomes moist due to presence of small quantity of water vapour caused by evaporation.
Then, pressure exerted by moist gas = pressure exerted by dry gas + pressure of water vapour (aqueous tension).
i.e. Pmoist = Pdry + f (aqueous tension)
or, Pdry = Pmoist – f
Therefore, aqueous tension should be subtracted from the total pressure to get pressure of the dry gas.