Description : (i) `NH_(3)` (ii) `N_(2)H_(4)` (iii) `HN_(3)` (iv) `PH_(3)` (v) `H_(2)S` (vi) `AsH_(3)` (vii) `SbH_(3)` (viii) `H_(2)Se` (ix) `H_(2)Te` Number of mole
Last Answer : (i) `NH_(3)` (ii) `N_(2)H_(4)` (iii) `HN_(3)` (iv) `PH_(3)` (v) `H_(2) ... lone pair of electrons on the central atom is present in pure s-orbital
Description : A student dropped few pieces of marble in dilute hydrochloric acid contained in a test tube. The evolved gas was then passed through lime water. What change would be observed in lime water? Write balanced chemical equation for both the change observed?
Last Answer : Answer. When dilute HCl is added to marble which is calcium carbonate, it forms calcium chloride, water and carbon dioxide. The chemical equation for the reaction is as follows: CaCO3 + 2HCl → CaCl2 + H2O ... reaction between lime water and carbon dioxide is as follows: Ca(OH)2 + CO2 → CaCO3 + H2O
Description : In a gas-liquid shell and tube heat exchanger, the (A) Presence of a non-condensable gas decreases the condensing film coefficient (B) Gases under high pressure are routed through the tube side, because high pressure ... water or steam condensate remain localised to the tubes (D) All 'a', 'b' & 'c'
Last Answer : (D) All 'a', 'b' & 'c'
Description : 2. The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should be the position of the object? -Physics-10
Last Answer : (d) The position of the object should be between the pole of the mirror and its principal focus.
Description : Water-tube boiler is the one, in which (A) Water passes through tubes and flue gases around it (B) Tube carrying hot flue gases are immersed in a pool of water (C) Tubes are placed in vertical position (D) None of these
Last Answer : Option A
Description : What happens when: a) When a mixture of sodium acetate and soda lime is heated in a hard glass test tube.
Last Answer : Methane gas is evolved. CH 3 COONA + NaOH CaO Na 2 CO 3 + CH 4 b) Methane is burnt in air or oxygen or methane undergoes complete combustion. It forms carbon dioxide and water. CO 2 + H ... ultraviolet light (sunlight). Organic product chloromethane is formed CH 4 + Cl 2 UV CH 3 Cl + HCl
Description : Accumulation of crystalline depositions in articular surfaces, bones, soft tissue, and cartilage is referred to as a) tophi. Tophi, when problematic, are surgically excised. b) subchondral bone. Subchondral ... refers to the escape of fluid from the blood vessels or lymphatics into the joint cavity.
Last Answer : a) tophi. Tophi, when problematic, are surgically excised.
Description : Air at dry bulb temperature Td1 is passed through the heating coil and some amount of air is by passed unaffected and leaves with dry bulb temperature Tb2 and the temperature of heated air is Td3 (where Td2 < Td3), what is the ... - Td1) / (Td2 - Td3) D. Bypass Factor = (Td2 - Td3) / (Td2 - Td1)
Last Answer : ANSWER : D
Description : What is observed (i) When a beam of light is pressed through a colloidal sol (ii) An electrolyte, NaCl is added to hydrated ferric oxide sol. (iii) Electric current is passed through colloidal sol.
Last Answer : Ans.: (i) Tyndal Effect (iv) Coagulation (v) Electrophoresis
Description : A __________ is a type of heat exchange system where water is heated to its' boiling point via combustion of a fuel blown through a tube submerged in water. a. Condensate loop b. Hyperbolic cooling tower c. Steam boiler d. All of above
Last Answer : c. Steam boiler
Description : Electricity is passed through water in electrolysis and two gases are formed. If one gas has a boiling point of -183 degrees and other has a boiling point of -253 degrees what are the gasses?
Last Answer : We know that the gas oxygen has a boiling point of about -183 degrees C. The gas hydrogen has a boiling point of about -253 degrees C.
Description : What kind of combustion is observed in alkanes? Why do air holes of a gas burner have to be adjusted when vessel being heated gets blackened by the flame? -Science
Last Answer : Alkanes are saturated hydrocarbons and generally burn in air with a blue, non-sooty flame. If the bottoms of the cooking vessels in our homes are getting blackened, it shows that the air holes of the gas stove are getting blocked and the fuel is not burning completely.
Description : During the preparations of hydrogen chloride gas on a humid day, the gas is usually passed through the guard tube containing calcium chloride. The role of the calcium chloride taken in the guard tube is to -SST 10th
Last Answer : C - Calcium chloride is a good dehydrating agent. It absorbs moisture or water content from the gas making it dry. Calcium chloride is widely used as a desiccant for drying gases and liquid hydrocarbons in many industries due to its ability to absorb water.
Description : Pick out the wrong statement: (A) The capacity of an evaporator is reduced by the boiling point elevation (B) Corrosive liquid is normally passed through the tubes in a ... recompression evaporator (D) Heat sensitive materials should be concentrated in high pressure evaporators
Last Answer : (D) Heat sensitive materials should be concentrated in high pressure evaporators
Description : When propyne is passed through hot iron tube at 400°C, it gives (a) Benzene (b) Toluene (c) m-Xylene (d) Mesitylene
Last Answer : Mesitylene
Description : When acetylene is passed through hot iron tube at 400°C, it gives (a) Benzene (b) Toluene (c) o-Xylene (d) Mesitylene
Last Answer : Benzene
Description : 1.12 litre dry chlorine gas at STP was passed over a heated metal when 5.56 g of chloride of the metal was formed. What is the equivalent weight of th
Last Answer : 1.12 litre dry chlorine gas at STP was passed over a heated metal when 5.56 g of chloride of ... formed. What is the equivalent weight of the metal ?
Description : Jam nut is a locking device in which (A) A smaller nut is tightened against main nut creating friction at the contacting surface (B) A split pin is passed through diametrically opposite slots in nut and ... parts of nut separated by slot (D) An elastic piece is tightened in the nut by a setscrew
Last Answer : (A) A smaller nut is tightened against main nut creating friction at the contacting surface
Description : Castle nut is a locking device in which (A) A smaller nut is tightened against main nut creating friction at the contacting surface (B) A split pin is passed through diametrically opposite slots in nut and ... of nut separated by slot (D) An elastic piece is tightened in the nut by a setscrew
Last Answer : (B) A split pin is passed through diametrically opposite slots in nut and a hole in bolt and the two ends of split pin are separated and bent back on nut
Description : The conditions for the discharge of electricity through gases in a discharge tube is _______.
Last Answer : The conditions for the discharge of electricity through gases in a discharge tube is _______. A. ... high pressure D. low potential and low pressure
Description : Which of the noble gases produced a colored glow when excited by electricity passing through a glass tube in which the gas is confined?
Last Answer : Neon has a red color.
Description : Fire tube boilers are those in which a) Flue gases pass through tubes and water around it b) Water passes through the tubes and flue gases around it c) Work is done during adiabatic expansion d) Change is enthalpy
Last Answer : a) Flue gases pass through tubes and water around it
Description : Water tube boilers are those in which a) Flue gases pass through tubes and water around it b) Water passes through the tubes and flue gases around it c) Work is done during adiabatic expansion d) Change is enthalpy
Last Answer : b) Water passes through the tubes and flue gases around it
Description : after atoms and molecules of gases and liquids are heated they move away from the heat . what takes their place?
Last Answer : ions
Description : Which one of the following gases is liberated when ethyl alcohol is heated with methyl magnesium iodide?
Last Answer : Which one of the following gases is liberated when ethyl alcohol is heated with methyl magnesium ... Methane B. Ethane C. Carbondioxide D. Propane
Description : It is easy to detect and monitor excess air a. As oxygen not used for combustion is heated and discharged with the exhaust gases. b. Oxygen is discharged without heating c. Both a. & b. d. None of above
Last Answer : a. As oxygen not used for combustion is heated and discharged with the exhaust gases.
Description : Phenol is heated with a solution of mixture of `KBr` and `KBrO_(3)`. The major product obtained in the above reaction is
Last Answer : Phenol is heated with a solution of mixture of `KBr` and `KBrO_(3)`. The major product ... Bromophenol C. 4-Bromophenol D. 2,4,6-Tribromophenol
Description : When a mixture containing phosphate is heated with conc. `HNO_(3)` and ammonium molybdated solution, a canary yellow precipitate is formed . The formu
Last Answer : When a mixture containing phosphate is heated with conc. `HNO_(3)` and ammonium molybdated solution, a canary yellow ... PO_(4). (NH_(4))_(2)MO_(4)`
Description : When a mixture of solid NaCl, solid `K_(2)Cr_(2)O_(7)` is heated with conc. `H_(2)SO_(4)` orange red vapours are obtained. These are of the compound
Last Answer : When a mixture of solid NaCl, solid `K_(2)Cr_(2)O_(7)` is heated with conc. `H_(2 ... B. chromyl chloride C. chromic chloride D. chromic sulphate
Description : P is an alcohl which on heating with `Al_(2)O_(3)` forms an alkene Q.Q on ozonolysis produces R and S. When the mixture of R and S is heated with NaOH
Last Answer : P is an alcohl which on heating with `Al_(2)O_(3)` forms an alkene Q.Q on ozonolysis produces R and S. When ... ))overset(|)(C)-CH_(2)-CH=O+CH_(2)=O`
Last Answer : P is an alcohl which on heating with `Al_(2)O_(3)` forms an alkene Q.Q on ozonolysis produces R and S. ... (|)overset(CH_(3))overset(|)(C)-CH=CH_(2)`
Last Answer : P is an alcohl which on heating with `Al_(2)O_(3)` forms an alkene Q.Q on ozonolysis produces R and S. ... (3))overset(|)(CH)-CH_(2)-COCl+CH_(3)MgCl`
Last Answer : Phenol is heated with a solution of mixture of `KBr` and `KBrO_(3)`. The major product obtained ... C. 4-Bromophenol D. 2, 4,6-Tribromophenol
Description : When a mixture containing `PCl_(3)` and `PCl_(5)` is heated with ethyl alcohol, a total of 4 moles of ehtyl chloride is formed. Mole ratio of `PCl_(3)
Last Answer : When a mixture containing `PCl_(3)` and `PCl_(5)` is heated with ethyl alcohol, a total of 4 moles of ehtyl chloride is ... : 1` C. `1 : 3` D. `2 : 1`
Description : A mixture of white powder and coke is heated in nitrogen gas very strongly. The product are
Last Answer : A mixture of white powder and coke is heated in nitrogen gas very strongly. The product are A. `Al_(2)O_(3),C_(2) ... D. `Al_(2)(CO_(3))_(3),N_(2)O`
Description : When egg albumin is heated till it is coagulated, the secondary and tertiary structures of the proteins are completely lost resulting in a mixture of randomly arranged (A) Dipeptide chains (B) Tripeptide chains (C) Polypeptide chains(D) All of these
Last Answer : Answer : C
Description : What does mixture of CS2 and H2S on passing over heated copper give?
Last Answer : Methane
Description : The wet and 'dry bulb temperature for a vapour-gas mixture are 25°C and 30°C respectively. If the mixture is heated to 45°C at constant pressure, the wet bulb temperature will be __________ °C. (A) 25 (B) > 25 (C) < 25 (D) - 25
Last Answer : (B) > 25
Description : When an unsaturated air-water mixture is heated at constant pressure, then (A) The partial pressure of water vapour increases (B) The specific humidity decreases (C) The relative humidity increases (D) The relative humidity decreases
Last Answer : D) The relative humidity decreases
Description : A mixture of phosphate rock __________ is heated in an electric furnace to produce phosphorous. (A) Salt & coke (B) Sand & coke (C) And coke (D) And sand
Last Answer : (B) Sand & coke
Description : A mixture of potassium chlorate, oxalic acid and sulphuric acid is heated. During the reaction which element undergoes maximum change in the oxidation number? (1) C (2) S (3) H (4) Cl
Last Answer : Cl
Description : List any two observations when Ferrous Sulphate is heated in a dry test tube? -Science
Last Answer : Two Observations Are: 1) Change in colour of crystals from green to white. 2) Evolution of gas. The gases evolved are SO2 and SO3.
Description : 2g of ferrous sulphate crystals are heated in a dry boiling tube. (i) List any two observations. (ii) Name the type of chemical reaction taking place. (iii) ‘Write the chemical equation for the reaction. -Chemistry
Last Answer : Answer. (i) •Green colour of Fe SO4 disappears and reddish brown solid is formed. • Smell of burning sulphur. (ii) Decomposition reaction
Description : Two inorganic compounds A and B were heated in a dry test tube. A evolved a colourless gas which turned lead acetate paper black and B evolved a gas w
Last Answer : Two inorganic compounds A and B were heated in a dry test tube. A evolved a colourless gas which turned lead acetate ... ` D. `S^(2-), NO_(3)^(-)`
Description : Air is to be heated by condensing steam. Two heat exchangers are available (i) a shell and tube heat exchanger and (ii) a finned tube heat exchanger. Tube side heat transfer area are equal in both ... steam on shell side (D) Shell and tube heat exchanger with air on shell side and steam inside tubes
Last Answer : (B) Finned tube heat exchanger with air outside and steam inside
Description : Write two precautions that must be taken while studying the decomposition reaction, when the ferrous sulphate crystals are heated in a boiling tube?
Last Answer : Answer. Keep your nose away from the gas like SO2 which is suffocative. Use tube holder to heat the test tube.