Answer
One molecule of $CO_2$ has a mass of $7.3\times 10^{-26}~kg$
Work Step by Step
A carbon atom consists of 6 protons and 6 neutrons.
An oxygen atom consists of 8 protons and 8 neutrons.
A molecule of $CO_2$ consists of 22 protons and 22 neutrons.
The mass of one molecule of $CO_2$ is $44~u$
We can find the mass of one $CO_2$ molecule:
$m = (44~u)(1.66\times 10^{-27}~kg/u) = 7.3\times 10^{-26}~kg$
One molecule of $CO_2$ has a mass of $7.3\times 10^{-26}~kg$
