The first-order reaction A→B takes place in an isothermal CSTR. The feed temperature is 20°C,
and the reactor is held at 120°C by heat exchange. A jacket is used to keep the temperature of the
reactor and this jacket is kept at this temperature by the water bath. The water bath is 40°C. The
temperature of the water bath was measured with PT100 and NTC, and 5 different data were
obtained.
Water bath
T(°C)
1
2
3
4
5
Pt100
40.3
41.2
39.8
40.5
42.0
NTC
41.1
39.7
41.7
40.1
40.2
a) Calculate the average, standard deviation, and percentage error for each measurement (12p)
b) Calculate the accuracy (3p)
c) Compare the precision, and accuracy of the devices and discuss the reasons (4p)
d) Suggest the most appropriate temperature measurement device (3p)
e) Explain the reasons for deviations from the actual temperature (3p)
Standard deviation: σ =
$$ \sqrt{\frac{1}{n} \sum_{i=1}^{n} d_i^2} $$
%Error =
$$ \frac{\sigma^2}{\bar{x}} $$
*100