The zero of the scale is calibrated using which of the following as the sample?
A. Air
B. Water
C. Inert gas
D. Pure nitrogen
Answer:D
The zero of the scale is calibrated using which of the following as the sample?
A. Air B. Water C. Inert gas D. Pure nitrogen
Explanation: The zero of the scale is calibrated using pure nitrogen as the sample. Optical filters are used to minimize effects of interfering gases.