X=percentage of Cl-35
(1-x)=percentage of Cl-35
35(x)+37(1-x)=35.454
35x+37-37x=35.454
-2x=35.454-37
-2x=-1.546
x=-1.546/(-2)
x=0.773
0.773=77.3/100=77.3%
(1-x)=1-0.773=0.227
0.227=22.7/100=22.7%
answer: the percentages are: 77.3% of Cl-35 and 22.7% of Cl-37.
Answer : Option B) 360 g/mol
Explanation : The antibacterial agent Penicillin N contains 8.92% of sulfur by mass. So we have to calculate the molar mass of penicillin N will be as
i) 256 X 0.0892 = 22.83 g/mol this cannot be the answer as it doesn't shows any sign of sulfur being present even in 1 mole.
ii) 360 X 0.0892 = 32.112 g/mol This is the closest to the molar mass of sulfur which is 32.06 g/mol; this means it contains 1 mole of sulfur.
iii) 390 X 0.0892 = 34.78 g/mol this also fails to prove the answer as correct.
iv) 743 X 0.0892 = 66.27 g/mol This is not even falling in the range of sulfur mole.
Hence we can confirm that the answer is Option B
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
.
Atomic mass is the number of protons + number of neutrons. 11 protons + 12 neturons = 23
Answer:
There are 5 neutrons in beryllium