PHYSICS-24-09- 11th (J-Batch)

REVIEW TEST-3 Class : XI (J-Batch) Time : 100 min Max. Marks : 75 General Remarks: INSTRUCTIONS 1. The question paper contain 15 questions and 20 pages. All questions are compulsory. Please ensure that the Question Paper you have received contains all the QUESTIONS and Pages. If you found some mistake like missing questions or pages then contact immediately to the Invigilator. 2. Each question should be done only in the space provided for it, otherwise the solution will not be checked. 3. Use of Calculator, Log table and Mobile is not permitted. 4. Legibility and clarity in answering the question will be appreciated. 5. Put a cross ( × ) on the rough work done by you. 6. Write your final answer(s) in the box given in the last of each question. Otherwise marks will NOT be awarded. Name Father's Name Class : Batch : B.C. Roll No. Invigilator's Full Name USEFUL DATA Atomic weights: Al = 27, Mg = 24, Cu = 63.5, Mn = 55, Cl = 35.5, O = 16, H = 1, P = 31, Ag = 108, N = 14, Li = 7, I = 127, Cr = 52, K=39, S = 32, Na = 23, C = 12, Br = 80, Fe = 56, Ca = 40, Zn = 65.4, Pt = 195, He = 4, Ba = 137 For Office Use ……………………………. Total Marks Obtained………………… Q.No 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Marks Q.1 Calculate rms velocity of a dust particle of mass 8.31×10–12 g at 329.3°C assuming kinetic theory of gases is applicable. [3] Q.2 A solution containing 2 moles each of Ba(OH)2, NH4Cl and KOH was divided into two equal parts and treated with V1L and V2L of HCl and NaOH respectively for complete neutralization. Calculate ratio V1 : V2 if molarity of HCl & NaOH solutions is in ratio 1 : 2. [3] Q.3 6 g of an organic compound on treatment with NaOH gave NH3 which when passed through 1 200 ml of 2 M H2SO4 completely neutralized it. Calculate % of nitrogen in the organic compound. [3] Q.4 A tube of uniform cross-section of length 100 cm is divided into two parts by a weightless and frictionless piston. One part contains 4 moles of hydrogen at 2 atm at equilibrium and other part contains 1 mole of nitrogen at the same temperature. Assume volume of piston to be negligible. (a) Calculate the length of each compartment if the tube was placed horizontally. (b) The tube is then held at angle of 45° with the horizontal keeping the nitrogen end upwards. Find the length of each compartment. [1.5+1.5] N2 compartment H2 compartment (a) Length (b) Length Q.5 A container holds 3L of N2(g) & liquid water at 300 K at a pressure of 1 atm. The water in 1 container is instantaneously split into H2 & O2 by electrolysis : H2O(l) H2(g) + 2 O2(g). After the completion of reaction, the total pressure was 1.698 atm. Calculate mass of water present in container. Aqueous tension of water at 300 K is 0.04 atm. [5] Q.6 A 7.38 L vessel containing N2 at 1 atm and 27°C is connected to a 8.21 L vessel containing N2 at 4 atm and 127°C. Keeping both vessels at their original temperatures, calculate (a) Final pressure (b) Amount of N2 in each vessel. [5] Q.7 A common method of working of temperature scales is by assigning temperatures for steam point (Boiling point of water) and ice point (melting point of water) or absolute zero. A temperature scale commonly used by engineers is the Rankine (R) scale on which absolute zero is 0 R and steam point is 671.4 R (a) Calculate ice point on Rankine scale. (b) Express 1800 R in Kelvin units. [5] Q.8 5 moles of a tetra-atomic non-linear gas 'A' at 10 atm & T K are mixed with 10 moles of another T gas B at 3 K & 5 atm in a closed, rigid vessel without energy transfer with surroundings. If final 5T temperature of mixture was 6 K, what is atomicity of gas B? Assume all modes of energy are completely manifested. [5] Q.9(a) Find molality of Ca2+ and NO in 2 M Ca(NO3)2 aqueous solution of density 1.328 g/mL. (b) Also find mole fraction of solvent in solution. [3+2] Q.10 Compressbility factor Z vs P plot for four real gases A, B, C & D are shown at 300 K (a) Out of gases A and B whose molecules are larger? Justify. (b) If slope of curve for B is 0.02 atm–1, calculate Van der Waals constant b for gas B. (c) Arrange Boyle temperatures (T) for gases A, B, C & D in increasing order. [2+2+2] Q.11 20 g mixture of Na2CO3, NaHCO3 and NaCl on heating to moderate temperatures produced 1.12 L of CO2 at NTP. 8 g of the same mixture in a different experiment required 80 ml of 1 M HNO3 for neutralization. Calculate mass % of each component in mixture. [6] Q.12 A gaseous mixture containing N2 & H2 in mole ratio 1 : 3 is used to carry out the reaction in a sealed container. N2 (g) + 3H2(g)  2NH3 (g) The total pressure was 0.8 atm at 25°C before the reaction. Determine final pressure at 323°C assuming 60% yield of reaction. [6] Q.13 Calculate (a) Number of nitrogen atoms in 160 amu of NH4NO3. (b) Number of gram-atoms of S in 490 kg H2SO4. (c) Grams of Al2(SO4)3 containing 3.2 amu of S. [6] Q.14 Calculate compressibility factor (Z) for 0.02 moles of a Van der Waals gas at pressure of 0.1 atm. Assume the size of gas molecules is negligible. Given: RT = 20 L-atm-mol–1 (T = Temperature of gas), a = 1000 atm-L2-mol–2 [6] Q.15 Three ideal gas samples in separate equal volume containers are taken and following data is given: Pressure Temperature Mean free paths Mol. wt. Gas A 1 atm 1600 K 0.16 nm 20 Gas B 2 atm 200 K 0.16 nm 40 Gas C 4 atm 400 K 0.04 nm 80 Calculate ratio (A : B : C) of following for the three gases. (a) Collision frequencies (Z11). (b) Number of collision by one molecule per sec. (Z1). (c) Average velocities. [3+3+2] A : B : C Z11 Z1 uavg