Answer:
The answer is 0.0698 M
Explanation:
The concentration was prepared by a serial dilution method.
The formula for the preparation I M1V1 = M2V2
M1= the concentration of the stock solution = 0.171 M
V1= volume of the stock solution taken = 200 mL
M2 = the concentration produced
V2 = the volume of the solution produced = 940 mL
Substitute these values in the formula
0.171 × 200 = 490 × M2
34.2 = 490 × M2
Make M2 the subject of the formula
M2 = 34.2/490
M2 = 0.069795
M2 = 0.0698 M ( 3 s.f)
The concentration of the Chemist's working solution to 3 significant figures is 0.0698M
Answer: 121.7558 amu
Explanation:
Average atomic mass of the unknown element =
(Mass of isotope 1 x Relative Abundance of Isotope 1) + ( Mass of Isotope 2 x Relative Abundance of Isotope 2)
(120.9 x 0.5721) + (122.9 x 0.4279) = 69.16689 + 52.58891
Average mass of the unknown element = 121.7558 amu
Proteins are made of carbon, hydrogen,oxygen, and nitrogen (CHON). Nucleic acids such as DNA and RNA contain carbon,hydrogen, oxygen, nitrogen, and phosphorus(CHON P). The body also needs trace amounts of other elements such as calcium,potassium, and sulfur for proper functioning of muscles, nerves, etc.
