Answer:
The correct option is a.
Explanation:
125 kPa
125kpa - 2x 4x x
Total pressure after reaction = 176 kPa
125 kPa - 2x + 4x + x = 176 kPa
x = 17
125 kpa - 2x = 125 kPa - 2(17) = 91 kPa
Initial pressure of the dinitrogen pentoxide ,(at t=0) =
Final pressure of the dinitrogen pentoxide, (at t = t) = P = 91 kPa
The rate constant is = 
It will take 113 minutes for the total pressure to reach 176 kPa.
Answer:
Red
Explanation:
Red color is evidenced when thymol blue indicator is in a solution having a pH of 11. A pH of 11 means that the solution is basic or alkaline. Therefore, the indicator turns red, indicating that the solution is alkaline.
When thymol blue indicator is in a acidic solution, the indicator remains blue.
The two liquids are different and so the melting points are different only because one represents an intermediate stage. It was a melting-point suppression effect, just like salt and ice, but it was much larger than anyone on the team had thought possible.
Answer : The labs were unable to reproduce the pharmaceutical company’s data.
Explanation : Any scientific claim must have reproducible experimental data. In this case, when the pharmaceutical company has the claim of reducing the cancer growth cells by 35% then by using the same manufacturing procedure for the drug and lab should be able to get this result. But they failed to match up with the results which clearly indicates that the labs were not able to produce the same results and hence they concluded that the pharmaceutical company's claims were invalid.
Answer:
The molar concentration of Cu²⁺ in the initial solution is 6.964x10⁻⁴ M.
Explanation:
The first step to solving this problem is calculating the number of moles of Cu(NO₃)₂ added to the solution:
n = 1.375x10⁻⁵ mol
The second step is relating the number of moles to the signal. We know the the n calculated before is equivalent to a signal increase of 19.9 units (45.1-25.2):
1.375x10⁻⁵ mol _________ 19.9 units
x _________ 25.2 units
x = 1.741x10⁻⁵mol
Finally, we can calculate the Cu²⁺ concentration :
C = 1.741x10⁻⁵mol / 0.025 L
C = 6.964x10⁻⁴ M
