Explanation:
Since HF is a weak acid, the use of an ICE table is required to find the pH. The question gives us the concentration of the HF.
HF+H2O⇌H3O++F−HF+H2O⇌H3O++F−
Initial0.3 M-0 M0 MChange- X-+ X+XEquilibrium0.3 - X-X MX M
Writing the information from the ICE Table in Equation form yields
6.6×10−4=x20.3−x6.6×10−4=x20.3−x
Manipulating the equation to get everything on one side yields
0=x2+6.6×10−4x−1.98×10−40=x2+6.6×10−4x−1.98×10−4
Now this information is plugged into the quadratic formula to give
x=−6.6×10−4±(6.6×10−4)2−4(1)(−1.98×10−4)−−−−−−−−−−−−−−−−−−−−−−−−−−−−√2x=−6.6×10−4±(6.6×10−4)2−4(1)(−1.98×10−4)2
The quadratic formula yields that x=0.013745 and x=-0.014405
However we can rule out x=-0.014405 because there cannot be negative concentrations. Therefore to get the pH we plug the concentration of H3O+ into the equation pH=-log(0.013745) and get pH=1.86
Answer:
Explanation:
rate of reaction
= -ve change in pressure of ethanol / time
= - (250 -237 )/100 = - 13 / 100 torr/s
= - 0.13 torr/s
next
- (237 - 224 )/100 = - 13 / 100 torr/s
= - .13 torr/s
next
- (224 - 211 )/100 = - 13 / 100 torr/s
= - .13 torr/s
so on
So rate of reaction is constant and it does not depend upon concentration or pressure of reactant .
So order of reaction is zero.
rate of reaction =K [C₂H₅OH]⁰
K is rate constant
K = .13 torr/s
In 900 s decrease in pressure
= 900 x .13 = 117
So after 900s , pressure of ethanol will be
250 - 117 = 133 torr
Hey there!:
Volume in mL :
1.71 L * 1000 => 1710 mL
Density = 0.921 g/mL
Therefore:
Mass = Density * Volume
Mass = 0.921 * 1710
Mass = 1574.91 g
