Why was the solution heated before it was left in an evaporating dish?

Why was the solution heated before it was left in an evaporating dish?
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What is the substance deposited in the bottom of the evaporating dish?

Description : What is the substance deposited in the bottom of the evaporating dish?

Last Answer : Generically it would be referred to as a residue. Its exactnature depends on what you evaporated.

What is the substance deposited in the bottom of the evaporating dish?

Description : What is the substance deposited in the bottom of the evaporating dish?

Last Answer : Generically it would be referred to as a residue. Its exactnature depends on what you evaporated.

In refrigerators, the temperature difference between the evaporating refrigerant and the medium being cooled should be (a) high, of the order of 25° (b) as low as possible (3 to 11°C) (c) zero (d) any value

Description : In refrigerators, the temperature difference between the evaporating refrigerant and the medium being cooled should be (a) high, of the order of 25° (b) as low as possible (3 to 11°C) (c) zero (d) any value

Last Answer : Ans: b

Spray dryer for evaporating milk to produce milk powder is made of (A) Lead lined steel (B) Stainless steel (C) Aluminium (D) Cast iron

Description : Spray dryer for evaporating milk to produce milk powder is made of (A) Lead lined steel (B) Stainless steel (C) Aluminium (D) Cast iron

Last Answer : (B) Stainless steel

__________ temperature is the steady state temperature attained by a small amount of liquid evaporating into a large quantity of unsaturated gas￾vapor mixture. (A) Dry bulb (B) Wet bulb (C) Dew point (D) None of these

Description : __________ temperature is the steady state temperature attained by a small amount of liquid evaporating into a large quantity of unsaturated gas￾vapor mixture. (A) Dry bulb (B) Wet bulb (C) Dew point (D) None of these

Last Answer : (B) Wet bulb

Steady state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is called the __________ temperature. (A) Dry-bulb (B) Wet-bulb (C) Dew point (D) Adiabatic saturation

Description : Steady state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is called the __________ temperature. (A) Dry-bulb (B) Wet-bulb (C) Dew point (D) Adiabatic saturation

Last Answer : (B) Wet-bulb

LMTD for evaporators & condensers for a given terminal parameters & set of conditions for counter-flow is equal to that for parallel flow. In such heat exchangers, with one of the fluids condensing or evaporating, the surface area required is the least in the __________ flow. (A) Parallel (B) Mixed (C) Counter flow (D) Same in either 'a', b' or 'c'

Description : LMTD for evaporators & condensers for a given terminal parameters & set of conditions for counter-flow is equal to that for parallel flow. In such heat exchangers, with one of the fluids condensing or evaporating, the surface ... Parallel (B) Mixed (C) Counter flow (D) Same in either 'a', b' or 'c'

Last Answer : (D) Same in either 'a', b' or 'c'

The effect that takes place which results in cooling action is1. Condensing 2. Heating 3. Cooling 4. Evaporating

Description : The effect that takes place which results in cooling action is1. Condensing 2. Heating 3. Cooling 4. Evaporating

Last Answer : Evaporating

When the bubbles of steam are produced? • Once the water reaches saturation temperature • Once the water starts evaporating • Once the temperature decreases • None of the above

Description : When the bubbles of steam are produced? • Once the water reaches saturation temperature • Once the water starts evaporating • Once the temperature decreases • None of the above

Last Answer : • Once the water reaches saturation temperature

Explain in detail evaporating still with its advantage and disadvantages.

Description : Explain in detail evaporating still with its advantage and disadvantages.

Last Answer : It consist of a hemispherical pan made from copper or stainless steel. It is surrounded by a steam jacket. Still is covered from top and connected to condenser. Hemispherical shape ... heat transfer is poor. Heating surface is limited. Not suitable for thermolabile material.

Describe the construction and working of evaporating pan with neat diagram.

Description : Describe the construction and working of evaporating pan with neat diagram.

Last Answer : Construction:  i. It consists of a hemispherical pan made from copper or stainless steel and surrounded by a steam jacket. ii. Hemispherical shape provides large surface area for evaporation. iii. ... . iv. After evaporation remove the product from product outlet. Diagram:

What are advantages of evaporating still?

Description : What are advantages of evaporating still?

Last Answer : It is simple to construct. Easy to clean and maintain. The vapors are condensed in it. It increases the speed of evaporation and the costly solvent can be recovered. E.g. ethyl alcohol ... to the operator. A vacuum pump can be fitted to the condenser for operation under reduced pressure.

Write the advantages & disadvantages of an evaporating pan

Description : Write the advantages & disadvantages of an evaporating pan

Last Answer : Advantages:   It is simple and cheap to construction.   Easy to clean and maintain.   Economical.  Disadvantages:   Poor coefficient of heat transfer.   Heating surface is ... concentration of thermolabile material.   Evaporating pan is open so vapour cause discomfort to the worker.

what is the vent onthe left side of the dish wsher for,kenmore elite,13922?

Description : what is the vent onthe left side of the dish wsher for,kenmore elite,13922?

Last Answer : who cares as long as it works

A circular plate, a cube and a sphere, all made up of same material and having the same mass, are heated to 300°C and left in a room. Which of them will have the slowest rate of cooling? (1) Circular plate (2) Cube (3) Sphere (4) All will cool at the same rate

Description : A circular plate, a cube and a sphere, all made up of same material and having the same mass, are heated to 300°C and left in a room. Which of them will have the slowest rate of cooling? (1) Circular plate (2) Cube (3) Sphere (4) All will cool at the same rate

Last Answer : (3) Sphere Explanation: In the late of 17th century British scientist Isaac Newton studied cooling of bodies. Experiments showed that the cooling rate is approximately proportional to the difference of temperatures between the heated body and the environment.

A circular plate, a cube and a sphere, all made up of same material and having the same mass, are heated to 300°C and left in a room. Which of them will have the slowest rate of cooling? (1) Circular plate (2) Cube (3) Sphere (4) All will cool at the same rate

Description : A circular plate, a cube and a sphere, all made up of same material and having the same mass, are heated to 300°C and left in a room. Which of them will have the slowest rate of cooling? (1) Circular plate (2) Cube (3) Sphere (4) All will cool at the same rate

Last Answer : Sphere

Are heated towel rails safe All of our electric towel rails are pre-filled with a water-based solution containing a mix of central heating preservatives. What is the best price of Towel Rail per Packet?

Description : Are heated towel rails safe All of our electric towel rails are pre-filled with a water-based solution containing a mix of central heating preservatives. What is the best price of Towel Rail per Packet?

Last Answer : Yes, our heated towel rails are safe. We have been manufacturing and selling Heated Towel Rails for nearly ten years and know what makes a great towel rail. If you are installing a heated ... will provide the correct heat output. Heated Towel Rails are now a common feature in modernized homes,

Phenol is heated with a solution of mixture of `KBr` and `KBrO_(3)`. The major product obtained in the above reaction is

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

When a mixture containing phosphate is heated with conc. `HNO_(3)` and ammonium molybdated solution, a canary yellow precipitate is formed . The formu

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)`

Phenol is heated with a solution of mixture of `KBr` and `KBrO_(3)`. The major product obtained in the above reaction is

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 obtained ... C. 4-Bromophenol D. 2, 4,6-Tribromophenol

When Bauxite is heated with NaOH solution, the water soluble compound formed is

Description : When Bauxite is heated with NaOH solution, the water soluble compound formed is

Last Answer : When Bauxite is heated with NaOH solution, the water soluble compound formed is A. `NaAlO_(2)` B. `Na_(3)AlO_(3)` C. `Al(OH)_(3)` D. `Al_(2)O_(3)`

A boiling water reactor is the one, in which the (A) Coolant water is allowed to boil in the core of the reactor (B) Coolant water, after being heated in the reactor core, generates steam in a boiler (C) Pressurised water is pumped into the core (D) Fuel and the coolant are thoroughly mixed to form a homogeneous solution

Description : A boiling water reactor is the one, in which the (A) Coolant water is allowed to boil in the core of the reactor (B) Coolant water, after being heated in the reactor core, generates steam ... water is pumped into the core (D) Fuel and the coolant are thoroughly mixed to form a homogeneous solution

Last Answer : (A) Coolant water is allowed to boil in the core of the reactor

A process stream of dilute aqueous solution flowing at the rate of10 Kg.s -1 is to be heated. Steam condensate at 95°C is available for heating purpose, also at a rate of 10 Kg.s -1 . A 1 - 1 shell and tube heat exchanger is available. The best arrangement is (A) Counter flow with process stream on shell side (B) Counter flow with process stream on tube side (C) Parallel flow with process stream on shell side (D) Parallel flow with process stream on tube side

Description : A process stream of dilute aqueous solution flowing at the rate of10 Kg.s -1 is to be heated. Steam condensate at 95°C is available for heating purpose, also at a rate of 10 Kg.s -1 . A 1 ... side (C) Parallel flow with process stream on shell side (D) Parallel flow with process stream on tube side

Last Answer : (A) Counter flow with process stream on shell side

Both white phosphorous as well as red phosphorous (A) Are soluble in CS2 (B) Burns when heated in air (C) Reacts with hot caustic soda solution to give Phosphine (D) All (A), (B), and (C)

Description : Both white phosphorous as well as red phosphorous (A) Are soluble in CS2 (B) Burns when heated in air (C) Reacts with hot caustic soda solution to give Phosphine (D) All (A), (B), and (C)

Last Answer : (B) Burns when heated in air

Which of the following carbohydrates will not give a red precipitate of Cu2O when heated with Benedict's solution? (a) Maltose (b) Glucose(c) Sucrose(d) Fructose

Description : Which of the following carbohydrates will not give a red precipitate of Cu2O when heated with Benedict's solution? (a) Maltose (b) Glucose (c) Sucrose (d) Fructose

Last Answer : Sucrose

What happens when ethanol is heated with acidified potassium dichromate solution? Write the chemical equation.

Description : What happens when ethanol is heated with acidified potassium dichromate solution? Write the chemical equation.

Last Answer : Answer. Ethanol is oxidised to ethanoic acid with the help of acidified K2Cr2O7. CH3CH2OH + 2O → CH3COOH + H2O

7. In a recombinant DNA technology a plasmid vector must be cleaved by a) the same enzyme that leaves the donor gene b) modified DNA ligase c) a heated alkaline solution d) four separate enzymes

Description : 7. In a recombinant DNA technology a plasmid vector must be cleaved by a) the same enzyme that leaves the donor gene b) modified DNA ligase c) a heated alkaline solution d) four separate enzymes

Last Answer : a) the same enzyme that leaves the donor gene

When an aldehyde is heated with Fehling's solution, the aldehyde undergoes one of the following processes. Does it undergo: w) neutralization x) oxidation y) reduction z) esterification

Description : When an aldehyde is heated with Fehling's solution, the aldehyde undergoes one of the following processes. Does it undergo: w) neutralization x) oxidation y) reduction z) esterification

Last Answer : ANSWER: X -- OXIDATION

How long do you've to ask for the same dish before?

Description : How long do you've to ask for the same dish before?

Last Answer : I think you have to wait for the server to say, “The usual?”. That’s when you will know it’s been long enough.

Sodium extract is heated with concentrated `HNO_(3)` before testing for halogens because :

Description : Sodium extract is heated with concentrated `HNO_(3)` before testing for halogens because :

Last Answer : Sodium extract is heated with concentrated `HNO_(3)` before testing for halogens because : A. Ag reacts ... )` and hence do not interfere in the test.

Which of the following is the best example of law of conservation of mass? [NCERT 1975] (A) 12 g of carbon combines with 32 g of oxygen to form 44 g of CO2. (B) When 12 g of carbon is heated in a vacuum there is no change in mass. (C) A sample of air increases in volume when heated at constant pressure but its mass remains unaltered. (D) The weight of a piece of platinum is the same before and after heating in air.

Description : Which of the following is the best example of law of conservation of mass? [NCERT 1975] (A) 12 g of carbon combines with 32 g of oxygen to form 44 g of CO2. (B) When 12 g of carbon is ... mass remains unaltered. (D) The weight of a piece of platinum is the same before and after heating in air.

Last Answer : (A) 12 g of carbon combines with 32 g of oxygen to form 44 g of CO2.