Gas weighing challenge

Absolute isotope ratios of carbon dioxide – a feasibility study

“…Furthermore, in our approach the calculation of the associated uncertainties is done via a Monte Carlo simulation, which leads to more reliable values of the best estimates and their associated uncertainties. Also, our improved buoyancy 49,50 correction is completely different. Our approach bears some advantages which justify further efforts to improve it.…”

“…At every time t x , it is important to record the ambient conditions, air pressure p, air humidity 4 and air temperature w. The masses of the two parent gases were then calculated using eqn (13a) and (13b), respectively. 49,50 In these two equations, r air,y is the air density at time t y , m are dened analogously, but during all these procedures, r stays evacuated. r cal is the density of the calibration weight used for calibrating the balance.…”

Solution to gas weighing challenge

“…This Analytical Challenge sets out to develop an equation to obtain mass of gases added to cylinders while accounting for buoyancy corrections [1]. The gas containers have tare masses, e.g., m s , encasing the inner volume V gas .…”

“…We assume that the densities of the two evacuated containers are the same within the limits of their uncertainties. We also assume that the ambient conditions (air temperature, humidity, and pressure) do not change significantly during weighing the two containers (for a better understanding of the applied weighing procedure, please see the figure 1 in the challenge [1]). At the time t 0 (before container "s" is filled with gas), both containers "s" and "r" are evacuated and weighed which provide the following equations:…”

“…Inserting the given quantities from the challenge [1] gives the following values: m A ¼ 0:9672 g and m B ¼ 1:0389 g ð27Þ…”