Platinum plus chlorine equals 0.889 grams whereas the platinum alone is 0.509grams so 0.509/0.889grams = 57% of the mass of the platinum plus chlorine. The chlorine would be 0.889-0.509=0.38 grams. The chlorine would make up about 42.7% of the total mass in grams.
The answer is B
I also did this quiz.
Answer:
At the second equivalent point 200 mL of NaOH is required.
Explanation:
at the first equivalent point:
H2A + OH- = HA- + H2O
initial mmoles y*100 y*100 - -
final mmoles 0 0 y*100 y*100
at the second equivalent point:
HA- + OH- = A2- + H2O
initial mmoles y*100 y*100 - -
final mmoles - - y*100 y*100
at the second equivalent point we have that y*100 mmoles of NaOH or 100 mL of NaOH ir required, thus:
at the second equivalent point 200 mL of NaOH is required.
Your answers would be, (Ex. 3*3*3*3....etc..).
(1), When measurements involving counting
(2), When measurement involves exactly defined quantities
Hope that helps!!!