Answer:
The atomic mass of phosphorus is 29.864 amu.
Explanation:
Given data:
Atomic mass of phosphorus = ?
Percent abundance of P-29 = 35.5%
percent abundance of P-30 = 42.6%
Percent abundance of P-31 = 21.9%
Solution:
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) + (abundance of 3rd isotope × its atomic mass / 100
Average atomic mass = (29×35.5)+(30×42.6) + (31×21.9) /100
Average atomic mass = 1029.5 + 1278 + 678.9/ 100
Average atomic mass = 2986.4 / 100
Average atomic mass = 29.864 amu.
The atomic mass of phosphorus is 29.864 amu.
0.16 M is the concentration of a solution prepared by diluting 20.0 ml of 2.00 M NaCl to 250.0 ml.
Explanation:
Data given:
Initial volume of NaCl, V1 = 20 ml
initial molarity of the NaCl solution = 2M
Final volume of the NaCl solution = 250 ml
final molarity of the diluted solution = ?
from the information given, the formula for dilution used is:
Minitial Vinitial = Mfinal Vfinal
putting the values in the rearranged equation:
V final = 
V final = 
Mfinal = 0.16 M
Thus it can be seen that when a 20 ml solution having molarity of 2M is diluted to 250 ml the molarity decreases to 0.16 M.
<span>The answer is B) A precipitate is formed. In the reaction Ni(No3)2)aq) + K2S(aq) -> NiS(s) + 2KNO3(aq), nickel(II) sulfide (NiS) is solid substance as indexed (s) while KNO3 is dissolved in water presented as index (aq). Therefore, if the reaction is successful, a precipitate (the solid substance NiS) will be formed,</span>
If you are talking about the element the element is phosphorus
