Description : Melting point & boiling points of liquid oxygen are respectively - 218.8°C & - 183°C, while the same for liquid nitrogen is - 210°C & - 195.8°C respectively. The difference in melting points of liquid oxygen & liquid nitrogen is not equal to 8.8 (A) °C (B) °F (C) °K (D) °R
Last Answer : (B) °F
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 : A liquid with high boiling point decomposes on simple distillation but it can be steam distilled for its purification .Explain how is it possible?
Last Answer : In steam distillation boiling occurs when vapour pressure of organic compound & steam becomes equal to atmospheric pressure. As vapour pressure of water is higher than the organic liquid. ... organic liquid vaporizes at a temperature below its boiling point in steam distillation without decomposing.
Description : Two liquids (A)and(B)are separated by fractional distillation, the boiling point of (A) is less than (B).which liquid comes out first in distillate? Explain.
Last Answer : The liquid (a) comes out first in distillate. On boiling the vapours of lower boiling component are formed first.
Description : Explain ,why an organic liquid vapourises at a temperature below its boiling point in steam distillation?
Last Answer : Because for boiling to occur vapour pressure of organic compound & steam should be equal to atmospheric pressure. As vapour pressure of water is higher than organic liquid. Therefore, organic liquid vaporizes at a temperature below its boiling point in steam distillation .
Description : Suggest a method to purify a liquid which decomposes at its boiling point.
Last Answer : The process Distillation under reduced pressure is used to purify a liquid which decomposes at its boiling point.
Description : Explain the following (a) The density of ice is less than that of liquid water? (b) The boiling point of water is less than that of H2S. (c) NaH has higher reducing character than H2O.
Last Answer : Ans-a) In structure of ice , Oxygen atom is tetrahedrally surrouneded by four hydrogen (with two hydrogen by hydrogen bond and with two hydrogen by covalent bond ) and have vacant spaces in ... Due to extensive hydrogen bonding in water c)NaH is ionic compound while water is a covalent compound
Description : Give reasons i) H2O is a liquid but H2S a gas. ii) Ammonia has higher boiling point than phosphine ii) Krypton & xenon make compounds.
Last Answer : Ans: i) Hydrogen bond is found in H2O but not in H2S. ii) Hydrogen bond is found in NH3 but not in PH3. iii) Because they have low ionization energy.
Description : Which one of the following statements most accurately relates the properties of a liquid at room temperature with its vapour pressure? A A liquid with a low vapour pressure will probably have a ... with a high vapour pressure will probably have high intermolecular forces and a low boiling point.
Last Answer : A A liquid with a low vapour pressure will probably have a high surface tension and a high boiling point.
Description : The boiling point of normal paraffinic (pron: pair-ah-FIN-ik) hydrocarbons increases with the number of carbon atoms per molecule. What is the smallest number of carbon atoms a normal paraffinic ... and still be a liquid at room temperature (70-75 degrees Fahrenheit) and 1 atmosphere pressure.
Last Answer : ANSWER: FIVE
Description : How many of the following properties increase down the group for nitrogen family (a) Atomic size (b) Acidic character of oxides (c) Boiling point of h
Last Answer : How many of the following properties increase down the group for nitrogen family (a) Atomic ... Metallic character (g) Basic character of hydrides
Description : What is nitrogen melting and boiling point?
Last Answer : Melting point −209.86°C; boiling point −195.8°C
Description : An organic liquid `A` containing `C,H` and `O` has a pleasant odour with a boiling point of `78^(@)C`. On boiling. A with conc. `H_(2)SO_(4)` a colour
Last Answer : An organic liquid `A` containing `C,H` and `O` has a pleasant odour with a boiling point of `78^(@)C`. On boiling ... . `C_(2)H_(5)OH` D. `C_(2)H_(6)`
Last Answer : An organic liquid `A` containing `C,H` and `O` has a pleasant odour with a boiling point of `78^(@)C`. On boiling ... . `C_(2)H_(6)` D. `C_(2)H_(5)OH`
Description : How do inter molecular forces affect the boiling point of a liquid?
Last Answer : What is the answer ?
Description : When a liquid is at its boiling point, no temperature change takes place due to heating. The energy supplied due to heating (a) Is used up to increase the potential energy of the liquid molecules (b ... c) Is used up to increase the kinetic energy and potential energy of the molecules (d) Is wasted
Last Answer : Ans:(a)
Description : The point at which the solid, liquid and gaseous forms of a substance co-exist is called its (a) boiling point (b) melting point (c) triple point (d) freezing point
Last Answer : Ans:(c)
Description : The point at which the solid, liquid and gaseous forms of a substance co-exist is called its (a) Boiling point (b) Melting point (c) Triple point (d) Freezing point
Description : Flash point of a liquid petroleum fuel gives an idea about its (A) Volatility (B) Explosion hazards characteristics (C) Nature of boiling point diagram (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Separating a substance from a mixture of liquid having I different boiling point is called?
Last Answer : Distillation
Description : The feed to fractionating column is changed from saturated vapour to saturated liquid. If the separation and reflux ratio remains unchanged, the number of ideal stages will (A) Increase (B) Decrease (C) Remain same (D) Depend on saturated boiling point; may increase or decrease
Last Answer : (A) Increase
Description : At the boiling point of the liquid at the prevailing pressure, the saturated absolute humidity becomes (A) 1 (B) 0 (C) ∞ (D) None of these
Last Answer : (C) ∞
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 : Leidenfrost point is a term concerned with the (A) Condensation of the saturated vapor on a cold surface (B) Concentration of a corrosive solution by evaporation (C) Heat transfer between two highly viscous liquids (D) Boiling of a liquid on a hot surface
Last Answer : (D) Boiling of a liquid on a hot surface
Description : Heat flux increases with temperature drop beyond the Leiden frost point in the plot of heat flux vs. temperature drop for a boiling liquid, because (A) Convection becomes important (B) Conduction becomes important (C) Radiation becomes important (D) Sub-cooled boiling occurs
Last Answer : (C) Radiation becomes important
Description : In sub-cooled boiling, (A) Temperature of the heating surface is less than the boiling point of the liquid (B) Temperature of the heating surface is more than the boiling point of the liquid (C) ... from heating surface are absorbed by the mass of the liquid (D) Very large vapour space is necessary
Last Answer : (B) Temperature of the heating surface is more than the boiling point of the liquid
Description : Pick out the wrong statement. (A) Heat transfer from a hot body to cold body by the emission of heat waves is called radiation (B) Filmwise condensation takes place on non-wettable surfaces (C) The ... of a solution is affected by liquid head as well as boiling point elevation (D) None of these
Last Answer : (B) Filmwise condensation takes place on non-wettable surfaces
Description : Pick out the wrong statement. (A) The value of hydrostatic head increases with increase in vacuum in the effect in a multiple effect evaporator system (B) Entering velocity of the liquid in ... a multiple effect evaporation system, the number of effects is limited by the total boiling point rise
Last Answer : (C) Duhring's plot is used for calculating the concentration of solution
Description : The temperature at which both liquid and gas phases are identical, is called the __________ point. (A) Critical (B) Triple (C) Freezing (D) Boiling
Last Answer : (A) Critical
Description : The point at which all the three (solid, liquid and gas) phases co-exist, is known as the __________ point. (A) Freezing (B) Triple (C) Boiling (D) Boyle
Last Answer : B) Triple
Description : __________ increases with increase in pressure. (A) The melting point of wax (B) The boiling point of a liquid (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : Use of water as a manometric liquid suffers from the disadvantage of its (A) Low vapour pressure (B) Corrosive nature (C) High vapour pressure (D) High boiling point
Last Answer : (C) High vapour pressure
Description : What refers to the state at which liquid and gaseous phases are indistinguishable? a. Triple point b. Critical point c. Boiling point d. Pour point
Last Answer : Critical point
Description : What is the unique state at which solid, liquid and gaseous phase can go co-exist in equilibrium? a. Triple point b. Critical point c. Boiling point d. Pour point
Last Answer : Triple point
Description : __________________ represents the highest pressure and highest temperature at which liquid and vapor can coexist in equilibrium. a) Critical Point b) Boiling Point c) Quality Point d) None of the above
Last Answer : Critical Point
Description : __________________ is a liquid at the saturations which has temperature equal to the boiling point corresponding to the existing pressure. a. Saturation Temperature b. Sub cooled Liquid c. Compressed Liquid d. Saturated Liquid
Last Answer : Saturated Liquid
Description : What is the amount of heat needed to turn 1kg of the substance at its boiling point from the liquid to the gaseous state? A. Heat of fusion B. Heat of vaporation C. Heat of condensation D. Heat of fission
Last Answer : Heat of vaporation
Description : The distillation carried out in such a way that the liquid with the lowest boiling point is first evaporated and recondensed, then the liquid with the next higher boiling point is then evaporated and ... is called A. cracking B. carbonisation C. fractional distillation D. full distillation
Last Answer : Answer: C
Description : The noble gases have low boiling points because: w) their ionization potentials are very low x) only weak Van der Waals forces hold the atoms together y) they are produced by the fractional distillation of liquid air z) they have eight electrons in the outer shell
Last Answer : ANSWER: X -- ONLY WEAK VAN DER WAALS FORCES HOLD THE ATOMS TOGETHER
Description : What is atomicity? What is the atomicity of phosphorus and nitrogen? -Chemistry 9th
Last Answer : Atomicity is the total number of atoms present in 1 molecule of a substance. The atomicity of nitrogen is 2 as N2 molecule contains 2 atoms. The atomicity of phosphorus is 4 as P4 molecule contains 4 atoms. ... exists as P4 & that of nitrogen is 2 as it is N2. Please like answer hope this helps u
Description : Organic chemistry involves molecules that contain which element? a. carbon c. oxygen b. nitrogen d. calcium
Last Answer : a. carbon
Description : Stringent anaerobes can be grown in a media by taking special measure as A.boiling the media for several minutes B.addition of cysteine C.passing through oxygen-free nitrogen D.any of these
Last Answer : D.any of these
Description : Stringent anaerobes can be grown in a media by taking special measure as A- boiling the media for several minutes B- addition of cysteine C- passing through oxygen-free nitrogen D- any of these
Last Answer : any of these
Description : The non-metal found in the liquid state is – (1) bromine (2) nitrogen (3) fluorine (4) chlorine
Last Answer : (1) bromine Explanation: Bromine belongs to the halogen group. It is the only non-metal element that is in a liquid form at room temperature. At room temperature it is a reddish brown fuming liquid with an unpleasant chlorine like smell.
Description : The gas which turns into liquid at the lowest temperature among the following is – (1) hydrogen (2) oxygen (3) helium (4) nitrogen
Last Answer : (1) hydrogen Explanation: Liquid hydrogen (LH2) is the liquid state, of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must ... method of obtaining liquid hydrogen involves a compressor resembling a jet engine in both appearance and principle.
Description : The non-metal found in the liquid state is (1) bromine (2) nitrogen (3) fluorine (4) chlorine
Last Answer : bromine
Description : Which of the following could be used as fuel in propellant or rockets ? (1) Liquid Hydrogen + Liquid Nitrogen (2) Liquid Oxygen + Liquid Argon (3) Liquid Nitrogen + Liquid Oxygen (4) Liquid Hydrogen + Liquid Oxygen
Last Answer : Liquid Hydrogen + Liquid Oxygen
Description : The gas which turns into liquid at the lowest temperature among the following is (1) hydrogen (2) oxygen (3) helium (4) nitrogen
Last Answer : hydrogen
Description : What is the boiling point of titanium ?
Last Answer : Titanium has a boiling point of 3277 degrees Celsius.