What is Hydration Enthalpy ?

1 Answer

Answer :

The amount of energy that is emitted when a mole of a compound is made into a dilute solution by dissolving the required number of gaseous positive and negative ions in a sufficient amount of water at an infinite distance is called hydration enthalpy of that compound. It is expressed by EH . M 2+ (g) + SO 4 2- (g) + H 2O (l) → M 2+ (aq) + SO 4 2- (aq) Hydration enthalpy is the sum of hydration enthalpy of cation and hydration enthalpy of anion. Hydration enthalpy is mainly dependent on ion charge. The greater the product of the number of charges, the greater the hydration enthalpy.

Related questions

Description : How does the of Hydration Enthalpy of alkaline earth metals vary & compare it with alkali metals

Last Answer : Ans The hydration enthalpies of alkaline earth metal ions decrease with increase in ionic size down the group. Be2+> Mg2+ > Ca2+ > Sr2+ > Ba2+ The hydration enthalpies of alkaline earth metal ions ... MgCl2 and CaCl2 exist as MgCl2.6H2O and CaCl2· 6H2O while NaCl and KCl do not form such hydrates.

Description : Which alkali metal will have highest hydration enthalpy ?

Last Answer : Ans. Li

Description : How does the of Hydration Enthalpy of alkaline earth metals vary & compare it with alkali metals  

Last Answer : The hydration enthalpies of alkaline earth metal ions decrease with increase in ionic size down the group. Be2+> Mg2+ > Ca2+ > Sr2+ > Ba2+ The hydration enthalpies of alkaline earth metal ... and CaCl2 exist as MgCl2.6H2O and CaCl2· 6H2O while NaCl and KCl do not form such hydrates.  

Description : Arrange the first group elements in the decreasing order of Hydration Enthalpy 

Last Answer : The hydration enthalpies of alkali metal ions decrease with increase in ionic sizes. Li+ > Na+ > K+ > Rb+ > Cs+

Description : If my drink is 3/4 water and 1/4 alcohol, am I getting hydration from the water?

Last Answer : I am going to say no. Alcohol interferes with your body’s water regulation systems, and causes your body to produce more urine than normal, no matter the amount of alcohol you drink.

Description : Should I buy a hydration pack to ride 8-10 miles on my bike?

Last Answer : I don't think you need to buy a hydration pack for a ride that's 8-10 miles. My dad is really into cycling and he only uses that if he goes on a long trip like across the state. I think you ... it also depends on what you think, if you know you drink a lot of water then go for the hydration pack.

Description : Is the hydration pack supposed to keep my water fresh?

Last Answer : One would like to think so!

Description : One moles of anhydrous `AB` dissolves in water and liberates `21.0 J mol^(-1)` of heat. The valueof `DeltaH^(Theta)` (hydration) of `AB` is `-29.4 J m

Last Answer : One moles of anhydrous `AB` dissolves in water and liberates `21.0 J mol^(-1)` of heat. The valueof `DeltaH^(Theta) ... mol^(-1)` D. `-8.4 J mol^(-1)`

Description : Assertion :- Lyophilic sol coagulate by adding other solvent. Reason :- Lyophilic sol are stable due to hydration energy.

Last Answer : Assertion :- Lyophilic sol coagulate by adding other solvent. Reason :- Lyophilic sol are stable due to ... D. If both Assertion & Reason are False.

Description : The compound that would undergo hydration very easily is

Last Answer : The compound that would undergo hydration very easily is A. `CH_(3)COCH_(2)Cl` B. `CH_(3)CH_(2)CHO` C. `Cl_3C-CHO` D. `Cl_(3)C CH_(2)COCH_(3)`

Description : Arrange the following compounds in decreasing orders of rate of hydration. `(X) C Cl_(3)CHO " " (Y) CH_(3)CHO " " (Z)CH_(3)COCH_(3) " " (W) CF_(3)CHO`

Last Answer : Arrange the following compounds in decreasing orders of rate of hydration. `(X) C Cl_(3)CHO ... . WgtZgtXgtY B. WgtXgtYgtZ C. WgtYgtZgtX D. WgtZgtYgtX

Description : Arrange the following compounds in decreasing orders of rate of hydration. `(X) C Cl_(3)CHO " " (Y) CH_(3)CHO " " (Z)CH_(3)COCH_(3) " " (W) CF_(3)CHO`

Last Answer : Arrange the following compounds in decreasing orders of rate of hydration. `(X) C Cl_(3)CHO ... . WgtZgtXgtY B. WgtXgtYgtZ C. WgtYgtZgtX D. WgtZgtYgtX

Description : What is the first stage of hydration in cement?

Last Answer : Need answer

Description : How much water do I need for proper hydration?

Last Answer : Everyone's body is different and it is hard to determine how much water an individual needs per day. It is recommended that you at least drink 6-8 glasses per day at a minimum.

Description : What are the benefits to adding Nathan hydration packs to my training?

Last Answer : Hydration packs are great under certain conditions. If you need both of your hands free this is the viable option. Rather than holding a water bottle in your hand while running.

Description : Which sports drink helps most with hydration?

Last Answer : The original rehydration drink, Gatorade, is actually one of the best. It can be diluted with water to make it less sugary, but still have enough electrolytes to replace those lost during sweating.

Description : How important is hydration?

Last Answer : Although water is the best way to stay hydrated, there are other methods which will work almost as well. There are sports drinks such as Gatorade, but they can do more harm than good. try eating watermelon or cucumbers before running. both of these fruits are high in water content

Description : Dry seeds endure higher temperature than germinating seeds as (A) Hydration is essential for making enzymes sensitive to temperature (B) Dry seeds have a hard covering (C) Dry seeds have more reserve food (D) Seedlings are tender

Last Answer : Answer : A

Description : When water itself combines chemically with some element or mineral it is called – (1) Carbonation (2) Desilication (3) Hydration (4) Oxidation

Last Answer : (3) Hydration Explanation: When water combines chemically with other elements, the process is called hydration. In organic chemistry, a hydration reaction is a chemical reaction in which a hydroxyl ... runs in a strong acidic, aqueous solution. Hydration leaves the non-water component intact.

Description : Setting of plaster of paris involves – (1) dehydration process (2) hydration to form other hydrates (3) oxidation process (4) reduction process

Last Answer : (2) hydration to form other hydrates Explanation: The setting of plaster of Paris takes place by hydration due to the formation of a solid crystalline hydrate and hardening of Plaster of Paris is ... . A slight expansion takes place in the process and heat is evolved. This process is exothermic.

Description : Setting of cement is due to the hydration of calcium silicates and?

Last Answer : Calcium aluminates

Description : Acetaldehyde is produced by hydration of acetylene in a sulphuric acid solution of mercuric sulphate. Hydration tower is made of (A) Rubber lined mild steel (B) Lead lined mild steel (C) Aluminium (D) Cast iron

Last Answer : (A) Rubber lined mild steel

Description : Atmospheric corrosion of metals result from their (A) Slow oxidation (B) Fast oxidation (C) Fast hydration (D) Slow dehydration

Last Answer : (A) Slow oxidation

Description : The remains of salt over the soil after evaporation of water is known as a. water logging b. salivation c. dehydration d. hydration

Last Answer : d. hydration

Description : Water supply through pipelines and tube wells to farm is known as a. fertilization b. hydration c. irrigation d. pollination

Last Answer : c. irrigation

Description : What is the major product from the acid-catalyzed hydration of 2-methyl-2- pentene? (a) 2-methylpentane (b) 2-methyl-1-pentanol (c) 2-methyl-2-pentanol (d) 2-methyl-3-pentanol

Last Answer : 2-methyl-2-pentanol

Description : Hollander beater used during paper pulp manufacture does not facilitate the __________ of fibre. (A) Cutting (B) Fibrillation (C) Hydration (D) Strengthening

Last Answer : (D) Strengthening

Description : Hollander beater' machine used in the paper manufacturing plant does not accomplish the task of (A) Final rolling out of paper (B) Cutting of fibres (C) Hydration of fibres (D) Fibrillation of fibre

Last Answer : (A) Final rolling out of paper

Description : Cement setting under water employs a/an __________ process. (A) Hydration (B) Decomposition (C) Oxidation (D) Reduction

Last Answer : (A) Hydration

Description : What is the major product from the acid-catalyzed hydration of 2-methyl-2- pentene? (a) 2-methylpentane (b) 2-methyl-1-pentanol (c) 2-methyl-2-pentanol (d) 2-methyl-3-pentanol

Last Answer : 2-methyl-2-pentanol

Description : Hydration of 2-methyl-1-propene (with H2O/H2SO4) gives : (a) CH3CH2CH2OH (b) (CH3)3COH (c) CH3CH2CH2CH2OH (d) (CH3)2CHOH

Last Answer : (CH3)3COH

Description : Setting of plaster of Paris is accompanied with (A) Hydration (B) Dehydration (C) Hydrolysis (D) Loss of CO2

Last Answer : (A) Hydration

Description : Hydrolysis of sugar is called (A) Hydration (B) Inversion (C) Esterification (D) None of these

Last Answer : (B) Inversion

Description : An oil is converted into fat by its (A) Hydrogenation (B) Hydrolysis (C) Hydrocracking (D) Hydration

Last Answer : (A) Hydrogenation

Description : __________ of quicklime produces slaked lime. (A) Hydration (B) Dehydration (C) Hydrogenation (D) None of these

Last Answer : (A) Hydration

Description : Chemical weathering of soil is caused due to (A) Oxidation (B) Carbonation (C) Hydration (D) All the above

Last Answer : Answer: Option D

Description : When each particle of aggregates is thinly coated with cement paste, a heterogeneous solid is formed, which is known as (A) Hydration (B) Gel (C) Concrete (D) None of these

Last Answer : Answer: Option C

Description : How dissolution takes place by hydration?

Last Answer : Ans: When an ionic compound is dissolved in water+ve hydrogen atoms of water molecule surrounds the –ve ions of solute, & -ve oxygen atoms surrounds the +ve ions and thus hold it in the dissolved form. This process is called hydration.

Description : Hydration of cement is due to chemical action of water with (A) Tricalcium silicate and dicalcium silicate (B) Dicalcium silicate and tricalcium aluminate (C) Tricalcium aluminate and tricalcium alumino ferrite (D) All the above

Last Answer : Answer: Option D

Description : The condition not applicable to water cement ratio law, is (A) Internal moisture conditions on hydration continue till complete strength is gained (B) Concrete specimens may be tested at any temperature (C) Concrete specimens need be of same age (D) Concrete specimens need be of same size

Last Answer : Answer: Option B

Description : Addition of pozzolana to cement (A) Decreases workability (B) Increases strength (C) Increases heat of hydration (D) None of these

Last Answer : Answer: Option D

Description : Addition of pozzolana to cement causes (A) Reduction in permeability (B) Loss of heat of hydration (C) Reduction in bleeding (D) All the above

Last Answer : Answer: Option D

Description : Pick up the correct statement from the following: (A) The concrete gains strength due to hydration of cement (B) The concrete does not set at freezing point (C) The strength of concrete increases with its age (D) All the above

Last Answer : Answer: Option D

Description : Pick up the incorrect statement from the following: (A) Tricalcium silicate (C3S) hydrates rapidly (B) Tricalcium silicate (C3S) generates more heat of hydration (C) Tricalcium silicate (C3S) develops early strength (D) Tricalcium silicate (C3S) has more resistance to sulphate attack

Last Answer : Answer: Option D

Description : Di-calcium silicate (C2S) (A) Hydrates rapidly (B) Generates less heat of hydration (C) Hardens rapidly (D) Provides less ultimate strength to cement

Last Answer : Answer: Option B

Description : Pick up the correct statement from the following: (A) Water cement paste hardens due to hydration (B) During hardening cement binds the aggregates together (C) Cement provides strength, durability and water tightness to the concrete (D) All the above

Last Answer : Answer: Option D

Description : ick up the incorrect statement from the following: (A) Admixtures accelerate hydration (B) Admixtures make concrete water proof (C) Admixtures make concrete acid proof (D) Admixtures give high strength

Last Answer : Answer: Option A

Description : Tricalcium aluminate (C3A) (A) Reacts fast with water (B) Generates less heat of hydration (C) Causes initial setting and early strength of cement (D) Does not contribute to develop ultimate strength

Last Answer : Answer: Option B

Description : Concrete gains strength due to (A) Chemical reaction of cement with sand and coarse aggregates (B) Evaporation of water from concrete (C) Hydration of cement (D) All the above

Last Answer : Answer: Option C

Description : Pick up the incorrect statement from the following: (A) The degree of grinding of cement, is called fineness (B) The process of changing cement paste into hard mass, is known as setting of ... (D) The heat generated during chemical reaction of cement with water, is known as heat of hydration

Last Answer : Answer: Option C