Chemistry homework of XII

1) How is nitro benzene prepared in laboratory? What happens when nitro benzene is reduced in acidic, alkaline and electrolytic conditions?
2) Discuss any one method that can be used for separation of primary , secondary and tertiary amines .
3.Define the terms :i)Normality factor ii)Primary standard solution iii)Acidity of a base iv)Indicator
4) 4gm of NaOH was added to 20 cc of 2N H2SO4 solution and the volume was diluted to one litre. Predict whether the dilute solution is acidic, basic or neutral and also calculate the resulting normality of the dilute solution in terms of gm/litre.
5) State and explain Hess’s law of constant heat summation.
6) Define Gibb’s free energy .Derive an expression to relate Gibb’s free energy change with useful work.
7) What is the physical concept of entropy? Predict the criteria of spontaneity in terms of entropy change and free energy change .
8) What is entropy of fusion ? Derive the relationship between Gibb’s free energy change and entropy change and also predict the criteria of spontaneity.
 To be submitted on given time

Chemistry homework of XI

1.Calculate the amount of lime (CaO) that can be prepared by heating 200 kg of lime stone (CaCO3) that is 95% pure.
2.Give a reaction to show that nascent hydrogen is more powerful reducing agent than molecular hydrogen.
3.Distinguish between metal and metalloid  with one example for each.
4.Define Avogadro 's hypothesis. How is this hypothesis applied to show that molecular mass of a volatile substance is twice of its vapour density?
5.Sketch a well labelled diagram for the manufacture of ammonia by Haber's process. Write the physical and chemical principles involved in it. Why can't ammonia be dried by passing over conc. Sulphuric acid?
6.Give a brief account of the following terms :i) Concentration of ore ii)Smelting process
7.State Boyle's law and Charle's law. Derive the relation PV = nRT. Two miles of ammonia are enclosed in a five litre flask at 27 degree Celsius. Calculate the pressure exerted by the gas assuming that the gas behaves like an ideal has.

To be submitted on given time

Chemistry homework of XII

1.What is normality? How is it related with molarity?
2.What is the normality of 20 cc of 2M phosphoric acid?
3.Define the following terms:  i) End point ii) Equivalence point iii)Indicator iv)Basicity of acid
4.If 20 ml of 0.5 N NaOH is mixed with 30 mL of 0.3 N HCl , is the resulting solution acidic or basic? Calculate the normality with respect to the acidic or basic final solution.
5.State whether the following properties are extensive properties or intensive properties: (a) Entropy  (b) Temperature
6.Define enthalpy of combustion. Enthalpy of formation of benzene is 55 KJ , enthalpy of formation of water and carbon dioxide are - 395KJ and  - 285 KJ respectively.  Calculate the enthalpy of combustion of benzene.
7.Why is - NO2 group a meta directing towards electrophilic aromatic substitution?
8.What are amines ? How are they classified?  Describe a suitable method for the separation of amines from their mixture.
9.State and explain Hess’s law of constant heat summation. Write it's one application.
 To be submitted on given time

Chemistry homework of XI

1.Calculate the percentage of S in Na2S2O3 (Na =23, S =32, O =16)
2.Calculate the number of moles of CO2 molecules in 2.24 mL of CO2 at NTP .
3.Distinguish between alloys and amalgam. Give one example for each.
4.State Avogadro' s hypothesis.
5.At what condition the value P x V is always constant?
6.Define universal gas constant and derive its value in SI unit.
7.State Boyle's law and Charle's law and derive ideal gas equation.
8.What do you mean by redox reaction?Justify with an example.
9.Describe the principle involved in the manufacture of ammonia by Haber' s process.

 To be submitted on given time

REGARDING UWC (United World Colleges) SCHOLARSHIP FOR SLC PASSED STUDENTS

Dear Krishna sir,

Following up on the phone conversation our team member had with your staff, I'd like to share information on United World College Scholarships:

...

UWC (United World Colleges) is a global education movement (of 17 different UWCs in 17 countries) that makes education a force to unite people, nations and cultures for peace and a sustainable future. Academically, UWC education is equivalent to 11th and 12th level education but defining UWCs goes higher and beyond academics. 

Every year a few full and partial scholarships are offered for Nepali students. Attend this orientation offered by UWC Nepal National Committee if you are an interested applicant (completed 10th grade) or a teacher who'd like to encourage deserving students to apply this year and beyond.

At the orientation we will talk about:

1) What UWCs are
2) Glimpses of UWC Life from UWC Alumni
3) Application and selection processes
4) Q/A from the audience

Please note that all candidates interested in UWCs do not apply directly to the colleges and must go through the selection process carried out by UWC Nepal National Committee. Ones who cannot attend the session are encouraged to go through www.uwcnepal.org.np for detailed information.

Scholarship application deadline: September 15, 2017

Website: www.uwcnepal.org.np

Application forms: http://uwcnepal.org.np/how-to-apply/

FB page: UWC Nepal (https://www.facebook.com/UWCNepalNationalCommittee/)

UWC Kathmandu Orientation event for information and Q and A: 

Date: Saturday, September 2, 2017

Time: 10:30 am

Venue: GAA Hall Thamel (Location map: https://tinyurl.com/y8x2aqyw)

More info: https://www.facebook.com/events/885093811656581/) 

As an Alumnae of the program, I personally highly recommend it to any candidate who sees himself/herself as an all rounder, someone with competence in academics, but also keen on learning and serving beyond the classroom through extracurriculars, outdoor and team activities as well as social work. I look forward to your kind support in getting this information to this scholarship to the students who deserve to know about it.

Regards,

Mona Aditya

Lester B. Pearson United World College, Canada graduate (2005-2007)

Contact no.: 9860164331

PHYSICS HW TO BE SUBMITTED ON BHADRA 20 BY CLASS XII STUDENTS

1. How are stationary waves formed?

2. If you are moving on the moon surface, can you hear the cracking sound behind you? Explain.

3. Do sound waves undergo reflection, refraction and polarization phenomena? Explain.

4. Which type of wave propagates in liquid, explain.

5. Longitudinal waves cannot be polarized. Why?

6. Distinguish between light waves and sound waves.

1. Use the principle of superposition of two waves to find the position of displacement of nodes and antinodes in standing waves?

2. State and explain the stationary waves?

3. Define progressive wave. Derive progressive wave equation.

4. What do you mean by progressive wave equation? Derive progressive wave equation in terms of its wave vector and displacement.

5. What the principle of superposition is as applied to wave motion? Discuss, the result of superposing two waves of equal amplitude and same frequency travelling in opposite direction.

Physics HW to be submitted on Bhadra 19 by Class XI

1.What is SHM? Show that the motion of loaded vertical spring is SHM. Also find its time period.

a.   2. Two vectors A and B are such that Vector A -Vector B=Vector C and A-B=C. Find the angle between them.

b.   3. Why does the particle have a uniform velocity along X-axis? Explain

       

       4. A ball is projected horizontally from the top of building and is dropped with zero velocity from the same point at the same time, which one will hit the ground first

       6.  If the displacement of a particle in given by the equitation. y=6sin(wt+π) then calculate the velocity and acceleration of particle

       7. At what distance from the mean position is the K.E equal to P.E in S.H.M

       8. Define linear, superficial and cubical expansivity. Establish the relation between them.

        9.The density of silver at 0⁰C is 10310kg/m³ and the coefficient of linear expansion is 0.000019⁰C^–1. Calculate the density at 100⁰C