Answer:

Explanation:
Mass of one tablet = 20 mg
Mass of two tablets = 
Percent that is soluble in water = 40%
Mass of tablet that is soluble in water = 
So, mass of solute is 
Density of water = 1 kg/L
Volume of water = 1 L
So, mass of 1 L of water is 
PPM is given by

Hence, the concentration of iodine in the treated water
.
Answer:
There are 4 tryptophans in the protein.
Explanation:
According to question, protein contains one tyrosine residue and say x number of tryptophans.
Concentration of protein solution = 1.0 micromolar = 
Molar absorptivity of a protein solution : 


Length of the cuvette = l = 1.0 cm
Absorbance of protein solution at 280 nm = A = 0.024
( Beer-Lambert's law)

Solving for x :
x = 4
There are 4 tryptophans in the protein.
The answer is about 1/2 it rises very sloe
NaCl (Sodium chloride)
LiF (Lithium fluoride)
The scientific notation for 5,098.000 is 5.098000*10^(3).
Here the number also has 7 significant figures.
Hope this helps~