0% 0 Stoichiometry Quiz 5 1 / 50 Quartz is___________? All A., B. and C. Transformed to Cristobalite on heating above 1470?C Converted to Tridymite on firing between 870 to 1470?C Stable form of silica upto 870?C 2 / 50 Raoult?s law is obeyed by a ______ solution? Molar Saturated None of these Normal 3 / 50 Pick out the wrong statement ? Raoult?s law holds good for the solubility of polar gases in non-polar liquids Most of the hydrocarbons are non-polar Molecules with symmetrical arrangement (e.g., CH4 and CCl4) are non-polar Generally, non-polar compounds are chemically inactive, conduct electricity poorly and do not ionise 4 / 50 Pick out the wrong unit conversion of mass transfer co-efficient? 1 kg/hr.m2.atm= 0.98687 kg/hr. m .bar 1 kg/hr.m2 = 4.8823 lb/hr.ft2 1 lb/hr.ft3.atm. = 4.8182 kg/hr.m2.bar 1 lb/hr.ft2 = 4.8823 kg/hr.m2 5 / 50 Simultaneous doubling of the absolute temperature of a gas and reduction of its pressure to half will result in ______ in the volume of the gas? Doubling Fourfold increase 1/4th reduction No change 6 / 50 Saturated molal absolute humidity of the vapor-gas mixture depends upon the________? Both A. and B. Vapor pressure at dry bulb temperature Neither A. nor B. Total pressure 7 / 50 Pick out the wrong statement? Both B. and C. The solution containing equal masses of two liquids ?X? and ?Y? has the same mole fraction of? ?X? and ?Y? The evaporation of aqueous solution of glucose causes its molarity to increase Both the freezing point as well as boiling point of sea water is more than that of distilled water 8 / 50 Raoult?s law states that ?the equilibrium vapor pressure that is exerted by a component in a solution is proportional to the mole fraction of that component?. This generalisation is based on the assumption that the_________? Component molecules are non-polar and no chemical combination or molecular association between unlike molecules takes place in the formation of the solution Attractive forces between like and unlike molecules are approximately equal All A., B. & C. Sizes of the component molecules are approximately equal 9 / 50 Pick out the wrong statement? The effect of pressure on heat capacity of gases at pressure above one atmosphere and above the critical temperature is negligible The value of Cp of gases increases with increase in pressure, above atmospheric pressure The value of Cp at critical temperature and pressure reaches infinity All A., B., and C. 10 / 50 S.T.P. corresponds to __________? 760 torr & 0?C 1 atm. absolute pressure & 15.5?C 760 mm Hg gauge pressure & 15.5?C 101.325 kPa gauge pressure & 15.5?C 11 / 50 Pick out the wrong unit conversion of heat transfer co-efficient? 1 kcal/m2.hr.?C = 0.2048 BTU/ft2.hr. ?F. = 1.163 W/m2.?K 1 kcal/m2.hr.?K = 1.163 W/m2.?C 1 BTU/ft2.hr.?F = 4.88 kcal/m2.hr.?C = 20.44 kJ/m2.hr?C = 5.678 W/m2.?C 1 W/m2.?C = 0.1761 BTU/ft2.hr.?F. 12 / 50 Pick out the wrong statement? Clapeyron equation is given by dP/dT = (?/T) (VG ? VL); where, P = vapor pressure, T = absolute temperature, ? = latent heat of vaporisation, VG and VL = volumes of gas and liquid respectively At the boiling point of liquid at the prevailing total pressure, saturated absolute humidity is infinite Percentage saturation and relative saturation are numerically equal for an unsaturated vapor gas mixture Clausius-Clapeyron equation relates the latent heat of vaporisation to the slope of the vapor pressure curve 13 / 50 Silica bricks are never used for lining the__________? Beehive coke ovens Roof of open hearth furnace Dome of blast furnace stoves By-product coke ovens 14 / 50 Pick out the wrong unit conversion of thermal conductivity ? 1 BTU/ft2.hr.?F/inch = 1.488 kcal/m2. hr.?C/m 1 kcal/m.hr.?C = 0.672 BTU/ft.hr.?F = 1.163 W/m. ?K 1 BTU/ft2.hr.?F/ft = 1.488 kcal/m2. hr.?C/m 1 W/cm.?C = 85.985 kcal/m.hr.?C = 57.779 BTU/ft.hr.?F 15 / 50 Pick out the wrong unit conversion ? 1 kgf= 9.8 Newton 1 Pascal second = 10 poise 1 stoke = 1 m2/second 1 ppm = 1 ml/m3 = 1 mg/kg 16 / 50 Pick out the wrong statement? 1.2 gm atoms of carbon and 1.5 gm moles of oxygen are reacted to give 1 gm mole of carbon dioxide. The limiting reactant is carbon. The percent excess reactant supplied is 25 To make 100 kg of a solution containing 40% salt by mixing solution A (containing 25% salt) and solution B (containing 50% salt), the amount of solution A required is 40 kg A gas bubble at a pressure of Pg is passed through a solvent with a saturation vapour pressure of Ps. If the time of passage of the bubble is long and air is insoluble in the solvent, the mole fraction of solvent in the bubble will be equal to Ps/Pg A supersaturated solution of a sparingly soluble solute, at a concentration of C, is being fed to a crystalliser at a volumetric flow rate of V. The solubility .of the solute is C1. The output rate of solids from an efficient crystalliser is (C + C1) V 17 / 50 Pick out the wrong statement? Volume occupied by 9.034 x 1023 atoms of oxygen in ozone (O3) at NTP will be 11200 c.c When equal weights of oxygen and methane are mixed in an empty reactor at room temperature, then the fraction of total pressure exerted by the oxygen is 1/2 One kg mole of an ideal gas at N.T.P occupies 22400 Nm3 Ten times dilution of a normal solution (N) reduces its normality to N/10 18 / 50 Pick out the wrong unit conversion ? None of these 1 kPa = 100 bar 1 atm. = 760 mm Hg = 29.92 inch Hg = 14.7 psi = 1.013 bar = 1.013 kgf/cm2 1 mm Hg = 1 torr = 133.3 Pa 19 / 50 Pure aniline is evaporating through a stagnant air film of 1 mm thickness at 300 K and a total pressure of 100 KPa. The vapor pressure of aniline at 300 K is 0.1 KPa. The total molar concentration under these conditions is 40.1 mole/m3. The diffusivity of aniline in air is 0.74 ? 10-5m2/s. The numerical value of mass transfer co-efficient is 7.4 ? 10-3. Its units are_________? mole/m2.s.Pa cm/s m/s k.mole/m2.s.Pa 20 / 50 Pick out the wrong statement? For reducing spalling tendency, the refractory should be well fired and its porosity should be more Refractoriness under load (RUL) of a refractory is always less than its refractoriness Refractories used in muffle furnace should have low thermal conductivity The electrical resistivity of refractories drops rapidly with rise in temperature 21 / 50 Size range of the colloids particles is ___________? 500 ? 1000 microns 5 ? 200 milli-microns 10 ? 50 Angstrom 50 ? 200 microns 22 / 50 Pick out the wrong conversion formula for the conversion of weight units ? 1 U.S. ton = 907 kg = 0.907 tonne = 0.893 ton 1 ton = 2240 lbs = 1016 kg = 1.016 tonnes = 1.12 U.S. tons None of these 1 tonne = 1000 kg = 22.046 lbs 23 / 50 Raoult?s law is not applicable to the_____? Concentrated solutions Solutes which dissociate or associate in the particular solution Both B. & C. Solutions containing non-volatile solute 24 / 50 Roof of a basic electric furnace is made of _______ bricks? Chromite Silica Superduty fireclay None of these 25 / 50 Refractory bricks with lower permeability is produced by using __________? Finer grog size All A., B. and C. Higher moulding pressure Higher firing temperature 26 / 50 Solutions which distil without change in composition are called_________? Supersaturated Saturated Azeotropic Ideal 27 / 50 Refractory bricks having lower porosity have _______? High insulating properties Greater strength Low thermal conductivity Low heat capacity 28 / 50 Pick out the wrong statement? Atomic heat capacities of all solid elements decrease greatly with decrease in temperature, approaching a value of zero at absolute zero temperature, when in the crystalline state Atomic heat capacities of the crystalline solid elements are nearly constant and equal to 6.2 kcal/kg-atom according to the law of Petit and Dulong Generally, the heat capacities of compounds are lower in the liquid than in the solid state The heat capacity of a heterogeneous mixture is an additive property, but when solutions are formed, this additive property may no longer exist 29 / 50 Pure oxide refractories are generally monocrystalline in nature and are self bonded _______ bricks are generally used as moderator in nuclear reactors? Thoria Carborundum Beryllia Corundum 30 / 50 Pick out the wrong unit conversion ? 1 ton of TNT (tri-nitro-toluene) = 4.2 GJ (1G = 109) 1 Joule = 4.186 calorie 1 ft.lbf= 0.3238 calorie = 0.1383 kg.m = 1.356 J = 1.356 N.m 1 kcal = 3.968 BTU = 0.00116 kWh = 0.00156 hp 31 / 50 Presence of MgO in alumino-silicate refractories _______ its refractoriness ? Lowers Either A. or B.; depends on its quantity Does not affect Increases 32 / 50 Sodium _______ has inverted solubility curve i.e. its solubility increases with the lowering of temperature? Chloride Carbonate (monohydrate) Bisulphite Thiosulphate 33 / 50 Recycling in a chemical process facilitates_____? Increased yield Enrichment of product Heat conservation All A., B. & C. 34 / 50 Refractories subjected to alternate cycles of heating & cooling are liable to loose their resistance to___________? Slag attack CO attack Fusion under load Thermal spalling 35 / 50 Saturated solution of benzene in water is in equilibrium with a mixture of air and vapours of benzene and water at room temperature and pressure. Mole fraction of benzene in liquid is xB and the vapour pressures of benzene and water at these conditions are pv B and pv w respectively. The partial pressure of benzene in air-vapour mixture is__________? PvB xB.PvB (Patm ? Pvw)xB xB.Patm 36 / 50 Pick out the wrong statement? The standard heat of solution of the hydrate of a substance is the difference between the heat of solution of the anhydrous substance and its heat of hydration The integral heat of solution of either component cannot be calculated from heat of mixing data The average value of heat of neutralisation of dilute solutions of weak acids and bases is much less compared to that for strong acids and bases The accompanying enthalpy change, when a solute is dissolved in solvent, depends upon the nature & amount of the solute & the solvent, on the temperature & on the initial & final concentrations of the solution 37 / 50 Refractories used in/for _______ should have low thermal conductivity? Coke ovens Insulation Regenerators Muffle furnaces 38 / 50 Pick out the wrong statement ? None of these ?Reduced pressure? is the ratio of the existing pressure of a substance to its critical pressure ?Reduced volume? is the ratio of the existing molal volume of a substance to its critical molal volume ?Reduced temperature? of a substance is the ratio of its existing temperature to its critical temperature, both expressed on Celsius scale 39 / 50 Pure oxygen is mixed with air to produce an enriched air containing 50 volume % of oxygen. The ratio of moles of air to oxygen used is__________? 0.2 1.72 0.5 0.58 40 / 50 Pick out the wrong statement? Heat capacity of a diatomic gas is higher than that of a monatomic gas The binary mixture of a particular composition in both vapor and liquid state is known as an azeotropic mixture Equal volumes of Argon and Krypton contain equal number of atoms Total number of molecules contained in 22.4 litres of hydrogen at NTP is 6.023 x 1023 41 / 50 Pick out the wrong statement? Calcined magnesite is also called dead burnt magnesite Insulating refractories used in place of regular refractory bricks are usually called light weight refractories, and they have similar composition as heavy bricks Superduty fireclay bricks correspond to a pyrometric cone equivalent of 26-28 Graphite refractories are also called plumbago refractories 42 / 50 Real gases approach ideal behaviour at_____? High pressure & high temperature Low pressure & high temperature High pressure & low temperature Low pressure & low temperature 43 / 50 Solutions having the same osmotic pressure are called ______ solutions? Isotonic Ideal Dilute Saturated 44 / 50 Refractoriness/fusion points of ?Superduty? refractories is ______ ?C? > 1730 > 2000 1630-1670 1520-1630 45 / 50 Pick out the wrong unit conversion of calorific value? 1 kcal/kg = 1.8 BTU/lb = 4.186 kJ/kg 1 BTU/lb = 2.3 kcal/kg 1 BTU/ft3 = 8.9 kcal/m3 = 0.038 MJ/m3 1 kcal/m3 = 0.1124 BTU/ft3 46 / 50 Pick out the wrong unit conversion of temperature? ?F = (?C + 17.778) ? 1.8 ?R = 273 + ?F Temperature difference of 1?K = 1?C = 9/5?F ?C = (F- 32) ? 0.555 47 / 50 Pick out the wrong statement about the recycle stream in a process ? Recycling in a process stream helps in utilising the valuable reactants to the maximum with minimum loss of reactants Recycling in a process does not help in getting higher extent of reaction Recycling is exemplified by refluxing back a part of the distillate to the distillation column to maintain the quantity of liquid within the column The ratio of the quantity of a reactant present in the reactor feed of a recycling operation to the quantity of the same reactant entering the process as fresh feed is called combined feed ratio 48 / 50 Pick out the wrong unit conversion of heat transfer rate? 1 kcal/hr= 1.163 Watt 1 BTU/ft2.hr = 2.712 kcal/m2.hr 1 kcal/m2.hr = 0.3687 BTU/ft2.hr = 1.163 Watt/m2 1 Watt = 1.163 kcal/hr 49 / 50 Refluxing of part of the distillate in a fractionating column is a ?recycling operation?, aimed primarily at________? Yield enhancement None of these Product enrichment Heat conservation 50 / 50 Pick out the wrong statement? The difference between the existing temperature of a vapor and its saturation temperature (i.e.dew point) is called its ?degree of superheat? A vapor whose partial pressure is less than its equilibrium vapor pressure, is termed as a ?superheated vapor? The temperature at which a vapor is saturated is termed as the boiling point A vapor is termed as a saturated vapor, if its partial pressure equals its equilibrium vapor pressure Provide Your Information Your score is The average score is 0% LinkedIn Facebook Twitter 0% Restart quiz Send feedback Share on facebook Facebook Share on twitter Twitter Share on whatsapp WhatsApp PrevStoichiometry Quiz 4 Stoichiometry Quiz 6Next
