Answer:
The higher the temperature, the more soluble most ionic solids are in water
As you cool a saturated solution from high temperature to low temperature, solids start to crystallize out of solution if you achieve a supersaturated solution.
If you raise the temperature of a saturated solution, you can (usually) add more solute and make the solution even more concentrated.
Explanation:
For many ionic solids, solubility in water increases with increase in the temperature of the solution.
This implies that increasing the temperature allow more solute to dissolve in the solvent, supersaturation may be achieved by so doing. As the solution is cooled, the solid crystalizes out of solution hence the answers above.
Answer:
The correct answer is: d. The pKa of the chosen buffer should be close to the optimal pH for the biochemical reaction.
Explanation:
The buffer resist or maintain the change in pH in case of Acid or basic addition to the solution. The buffer capacity should be within one or two pH units when compared to the optimal pH.
Thus it is important to select a buffer with pKa close to the optimum pH of the reaction because the ability for the buffer to maintain the pH is is great at the pH close to pKa.
Answer:
The correct answer is entropy change of the surrounding plus the entropy change of the system must be positive.
Explanation:
The term entropy is a state function.Entropy can be defined as the disorder or randomness of the molecules in a system.
A spontaneous reaction is a type of reaction which deals with the release of free energy.The change of free energy in case of spontaneous reaction is always negative.
According to the second law of thermodynamics a spontaneous reaction will occur in a system if the total entropy of both system and surrounding increases during the reaction.
Answer:
Reaction 1 is balanced but 2 is not balanced , the balance equation are :
1. 
2.
Explanation:
Balanced Equations : These are the equation which follows the law of conservation of mass .
The total number of atoms present in reactant is equal to total number of atoms present in product.
1.
This is acid - base type reaction where
act as Acid
act as weak base
Reactant : ,
Number of atoms of :
C = 2 () + 1 ()
= 2 + 1
= 3
H = 4() + 1 ()
= 4 + 1
5
O = 2() + 3 ()
= 5
Na = 1 ()
= 1
Product : 
,
, 
Number of atoms :
C = 1() + 2()
= 1 + 2
= 3
H = 2() + 3()
= 2 + 3
= 5
O = 1() + 2()
+2(
= 1 + 2 + 2
= 5
Na = 1(
= 1
Number of Na =1 , C = 3 , H= 5 and O =5 in both reactant and product , so it is a balanced reaction
2.
This is double displacement reaction .
Check the balancing in both reactant and products should be :
Na = 2
H = 2
Ca = 1
C = 2
O = 6
Cl = 2
