Question

In: Chemistry

You are removing imidazole from your pooled nickel column samples by dialysis. The volume of the...

You are removing imidazole from your pooled nickel column samples by dialysis. The
volume of the pooled sample is 32 mL and the imidazole concentration is 0.5 M.

a. What is the concentration of imidazole after exposure to three consecutive dialyses
against 1 L of buffer?
b. If the imidazole at the start is 3.4% (w/v), what is the concentration in
weight percent at the end of the dialysis (three consecutive exposures to one liter
of buffer)?

Solutions

Expert Solution

(a). Volume of sample V1=32ml

Strength of imadazole initially S1=0.5M

Volume after 1st dialysis=1000ml + 32 ml (volume of buffer + sample)=V2

Strength of imadazole after 1st dialysis=S2.

Therefore, S1V1=S2V2=> 32(ml) * 0.5(M)/ 1032(ml)=S2=0.0155 M ( concentration after 1st dialysis)

For 2nd dialysis S1 becomes 0.0155 and V1= 1032 (present volume of sample + buffer)

V2= (1032+ 1000)ml= previous volume + volume of freshly added buffer=2032 ml.

Therefore, S1V1=S2V2=> 0.0155(M) * 1032(ml)/ 2032(ml) => S2= 0.0078 M (concentration after second dialysis)

Similarly, concentration after final and third dialysis= 0.0078 (M) * 2032(ml)/3032 (ml)= 0.005 (M)

(b) (w/v) percentage is defined as the mass of the solute(gms)/ volume of the total solution(ml)

Therefore, initially volume of total solution=32 ml= volume of sample + volume of imidazole in the solution.

Therefore, 3.4%= [mass of solute(gm)/32(ml)] * 100%=> mass of solute=1.088gm.

Therefore mass of solute always remains the same throughout the dialysis. Volume changes only and total volume of the sample after three dialysis= 32+1000+1000+1000= volume of sample+ 3 times the volume of buffer required for three dialysis.

Therefore (w/v) % after three dialysis= (1.088/3032) *100%= 0.036%


Related Solutions

You should use a pooled t-test versus a non-pooled t-test when the samples are matched. the...
You should use a pooled t-test versus a non-pooled t-test when the samples are matched. the variance of the two populations are equal. the sample sizes of both groups are the same. None of these the samples are matched and the sample sizes of both groups are the same.
Provided below are summary statistics for independent simple random samples from two populations. Use the pooled​...
Provided below are summary statistics for independent simple random samples from two populations. Use the pooled​ t-test and the pooled​ t-interval procedure to conduct the required hypothesis test and obtain the specified confidence interval. x1=12, s1=2.4, n1=19​, x2=13, s2=2.2​, n2=19 a.​ Two-tailed test, a=0.01 b. 99% confidence interval Part 1) First, what are the correct hypotheses for a​ two-tailed test? Part 2) ​Next, compute the test statistic. Part 3) Determine the​ P-value. Part 4) What is the conclusion of the...
Provided below are summary statistics for independent simple random samples from two populations. Use the pooled​...
Provided below are summary statistics for independent simple random samples from two populations. Use the pooled​ t-test and the pooled​ t-interval procedure to conduct the required hypothesis test and obtain the specified confidence interval. x1=15​, s1=2.3​, n1=15​, x2=16​, s2=2.2​, n2=15 a.​ First, what are the correct hypotheses for a​ two-tailed test? compute the test statistic. Now determine the critical values. What is the conclusion of the hypothesis​ test? Since the test statistic ____ in the rejection​ region, ____ H0 b....
Provided below are summary statistics for independent simple random samples from two populations. Use the pooled​...
Provided below are summary statistics for independent simple random samples from two populations. Use the pooled​ t-test and the pooled​ t-interval procedure to conduct the required hypothesis test and obtain the specified confidence interval. x1= 18, s1= 4, n1= 21, x2= 21, s2= 5, n2=13 a. What are the correct hypotheses for a​ left-tailed test? b. Compute the test statistic . c. Determine the​ P-value. d. The 90% confidence interval is from _____ to _______ ?
Summary statistics are given for independent simple random samples from two populations. Use the pooled t-test...
Summary statistics are given for independent simple random samples from two populations. Use the pooled t-test to conduct the required hypothesis test. 1 = 13, s 1 = 5, n 1 = 10,   2 = 21, s 2 = 4, n 2 = 14 Perform a left-tailed hypothesis test using a significance level of α = 0.05. a Test statistic: t = -1.526526 Critical value = -1.717 0.05 < P < 0.10 Do not reject H0 b Test statistic: t =...
You are considering an investment in nickel mines in Russia. Your expectations are that you will...
You are considering an investment in nickel mines in Russia. Your expectations are that you will take losses eventually, but once infrastructure is built, the project will become more profitable very quickly. You have estimated that the initial revenues will be $100 million per year and grow at a rate of 45% per year for four years. Due to political risk, you decide to use only a four-year horizon for planning purposes. Variable costs are expected to be 70% of...
The diameter of a nickel is 21 mm . How far from your eye must it...
The diameter of a nickel is 21 mm . How far from your eye must it be held so that it has the same apparent size as the moon? (Use the astronomical data inside the back cover of the textbook.)
Your firm has been asked to evaluate the "risk" of removing drums of acid from a...
Your firm has been asked to evaluate the "risk" of removing drums of acid from a waste lagoon that contains cyanide. The following data have been provided to you: Volume of air in which occupants live = 1 X 108 m3 Wind speed = calm Number of drums = 10 Volume of each drum = 0.02m3 Contents of drums: HCl at a concentration of 10% by mass Anticipated reaction : HCl + NaCN --> HCN(g) + NaCl RfC for HCN...
You are making a box by removing the corners from an 16cm by 10cm rectangular box....
You are making a box by removing the corners from an 16cm by 10cm rectangular box. How much do you need to remove to make a box of maximum value? Please show explanation
Ask Your Teacher A scale reads 344 N when a piece of nickel is hanging from...
Ask Your Teacher A scale reads 344 N when a piece of nickel is hanging from it. What does it read (in N) when it is lowered so that the nickel is submerged in water Please help solve, I need help with how to calculate. Thank you
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT