1.2 Nigerian crude oil was analyzed for vanadium concentration using visible spectrophotometry, and the following results (in ug/g) were obtained: 23.82, 24.01. 22.98.23.68, 23.97, 15.63.24.11. 23.59.22.87.28.99.22.88 and 24.08. If the true concentration of vanadium in the crude oil as determined by atomic absorption and energy dispersive X-ray fluorescence spectrophotometry techniques was 23.94 ug/g. Use the above information to calculate: (1) Absolute error (ii) Percentage relative error (iii) Average deviation (iv) Relative accuracy in parts per thousand () Probable error (vi) Standard error (or standard deviation of the mean) fuit) Average deviation of the mean (viii) Coefficient of variation (ix) Relative standard deviation in parts per thousand 6) Variance (xi) Comment on the Accuracy and Precision of the visible spectrophotometric technique used for the determination of vanadium in crude oil.
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nigerian crude oil vanadium
Answer:
ASSIGNMENT 1
Question 1
A standard serum sample containing 102 meq/L was analyzed by coulometric titration with silver ion. Duplicate results of 101 and 98 meq/L were obtained. Calculate
a) The absolute error of the mean b) The relative error in percent
ii. Calculate the uncertainty in the answers of the following
0.00006)
0.001)]
Question 2
a) Determination of sodium level in separate portions of a blood sample by ion selective electrode measurement gave the following results: 139.2, 139.8, 140.1, and 139.4 meg/l. what is the range within which the true value falls, assuming no determinate error
A) At the 90% confidence level
B) At the 95% confidence level
C) At the 99% confidence level
b) These replicate molarities were obtained when standardizing a solution: 0.1067.0.1071, 0.1066 and 0.1050. can one of the results be discarded as due to accidental error at the 95% confidence level?
Can any of the data in the problem above be rejected at the 95% confidence level.
Question 3
A batch of nuclear fuel pellets was weighed to determine if they fell within control guidelines. The weights were 127.2, 128.4, 127.1, 129.0, and 128.1g. calculate the mean, median and range.
ii. Replicate water samples are analyzed for water hardness with the following results: 102.2, 102.8, 103.1 and 102.3ppm CaCO3. Calculate
a) The standard deviation
b) The relative standard deviation c) The standard deviation of the mean
d) The relative standard deviation of the mean (in percent) of the individual results