Answer:
2.19 x 10^-12.
Explanation:-
The relation between Ka and Kb for an acid and it's conjugate base is
Ka x Kb = Kw where Kw = ionic product of water.
So Kb = 10^-14 / (4.57 x 10 ^ -3)
= 2.19 x 10^-12
Answer:
1.2,dibromoethane is the sha'awa .
Answer:
A) in response to an increase in the cytoplasmic Ca2+concentration.
Explanation:
Muscle contraction occurs in response to an increase in the cytoplasmic Ca2 + concentration.
This process occurs with the shortening of the sarcomeres resulting in a result, the actin filaments react with myosin, generating actomyosin. During this reaction, it is necessary to increase the cytoplasmic concentration of Ca + and ATP. In this, myosin will break down ATP, releasing energy so that the muscle can contract.
Answer: 1.8124 g of 3-nitrophthalhydrazide were recovered.
Explanation:
The balanced chemical reaction will be :

moles of 3-nitrophthalic acid = 
As 1 mole of 3-nitrophthalic acid gives = 1 mole of 3-nitrophthalhydrazide
0.0110 moles of 3-nitrophthalic acid gives =
mole of 3-nitrophthalhydrazide
mass of 3-nitrophthalhydrazide = 
As the percentage yield is 93% , the mass of 3-nitrophthalhydrazide recovered = 
Therefore 1.8124 g of 3-nitrophthalhydrazide were recovered.