Grade 11 final exam revision

revision for final exam Grade 11

1 markers

• State the le Chatelier's principle

• What do you mean by term “molarity”? How do you express it ?

• Explain the term disproportionation with an example

• How many spherical nodes do you expect in the 4s-orbital ?

• Explain why Cyclopentadienyl anion is aromatic ?

• State the the Heisenberg's uncertainty principle.

• Calculate the oxidation number of chromium in CrO5.

• Draw the structure of 2,2,4-trimethylpentane.

2 markers• What do you mean by metamerism ? Does butane

show metamerism ?

• What do you mean by inverse of Kc? Write an expression for it.

• Explain law of multiple proportions with an example to prove it.

• What do you mean by the term nucleophiles and electrophiles ? Explain.

• Two litres of an ideal gas at a pressure of 10 atm expands isothermally into a vacuum until its total volume is 10 litres. How much heat is absorbed and how much work is done in the expansion?

• Give the net ionic equation for the reaction of potassium dichromate (VI) with sodium sulphite in an acid solution to give chromium (III) ion and the sulphate ion.

3 markers

• i)  List two differences between Orbit and Orbital ii)  If an electron is moving with a velocity 600 m/s which

is accurate up to 0.005%n then calculate the uncertainty in its position.

• The species H2O, HCO3, HSO4- and NH3 can act both as

Bronsted acids and bases. For each case give the corresponding conjugate acid and base.

Value based question

• John was arrested by the custom officials as he was smuggling drugs and caught by x-ray machines. According to Roentgen when electrons strike a material in the cathode ray tube, it produces a ray which can cause fluorescence in the fluorescent material placed outside the cathode ray tubes. These rays were called x-rays. These were not deflected by electric and magnetic field. It was used as diagnostic tool in the treatment of diseases and bone fractures.

a)What is the approx. wavelength of x-rays?b)Why x-rays are used to screen luggage’s in airports? c) How would you prevent smuggling?

• What is inductive effect? Draw a resonating structure for phenol using the curved arrow notation.

• A gas decolorizes bromine water to give CH2=CH Br and CH3CHBr2 on treatment with one or two moles of HBr respectively. Identify the gas liberated and explain the reaction.

• 1) what is the relation of internal work to pressure? Derive it.

a)Draw the Andrews isotherms for CO2 gasb) what is compressibility factor ? explain through

mathematical explanation..2) Why will m-nitrobenzene and toluene which will

undergo nitration more easily and why ?• What do you mean by hybridisation. Explain the

various types of hybridization using ethane, ethene and ethyne explain each of them using diagrams.

• A) Why does –NO2 group present on benzene ring deactivate and m-directing in electrophilic substitution reaction?B) What are free radicals? How are they formed?

• Which of the following has dipole moment and why? 2,2-Dimethylpropane, trans-Pent-2-one, cis-Hex-2-ene,

2,2,3,3- Tetra methyl butane

5 mark questions• A 2.5 L flask contains 0.25 mol each of SO2 and N2 gas at

270 C. Calculate the partial pressure exerted by each gas and also the total pressure exerted by each gas and the total pressure. Name the law on which it is based.

• Describe with the help of chemical equations the following reactions: – a)  Friedel Craft’s alkylation – b)  Wurtz reaction – c)  Kolbe’s electrolysis reaction

• A) How many grams of KClO3 must be decomposed to prepare 3.36 litres of oxygen at STP?

B)State markovnikov’s rule C) What happens to internal energy of the system if i) work

is done on the system ii) Work is done by the system?

• For the equilibrium NOCl(g) ⇔ 2NO(g) + Cl2 (g) the value of the equilibrium constant, Kc is 3.75 x 10-6 at 1069 K. Calculate the Kp for the reaction at this temperature.

• Chalk out the mechanism for anti markovnikov’s rule

• State the Planck's quantum theory ?Write the electronic configuration for O2 molecule.A sample of 0.50g of organic compound was treated

according to Kjeldahl’s method. The ammonia evolved was absorbed in 25ml of 0.5 M H2SO4. The residual acid required is 30ml of 0.5M solution of NaOH for neutralization. Find the percentage composition of nitrogen in the compound.

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