Self-test 4.5

The spread of the parallel determination values is 0.15 %

The relative expanded uncertainty of nickel content in the sample is 0.22 %

The standard uncertainty of nickel content in the sample is 0.15 %

The relative expanded uncertainty of nickel content in the sample is 0.15 %

The relative expanded uncertainty of nickel content in the sample is 22 %

The true value of nickel content in the steel sample is surely between 6.60 and 6.90 %

The absolute expanded uncertainty of nickel content in the sample is 0.15 %

The expanded uncertainty of nickel content in the sample is 0.15 %

The relative expanded uncertainty of nickel content in the sample is 2.2 %

The true value of nickel content in the steel sample is between 6.60 and 6.90 % with approximately 95% probability.

The uncertainty of nickel content in the sample is 0.15 %

Manganese content in the water sample is (3.43 ± 0.43) mg/kg, k=3, norm. 

The measurement result of zinc content in potato sample is in range of 3.4…3.7 mg/kg with probability of approximately 68%. 

Iron content in the sample is 2.17 mg/kg with standard uncertainty of 0.05 mg/kg, k=2, norm.

c(Zn) = (2.7 ± 0.30) %, k=2, norm. 

Dissolved oxygen level in the water is 5.34 mg/l with combined standard uncertainty of 0.17 mg/l.

c(Pb) = (0.080 ± 0.0614) mg/kg, k=2, norm. 

c(Fe) = (5.85 ± 0.1) mg/kg, k=2, norm.