Relative Molecular Mass of Carbon Dioxide

44

The relative atomic mass of oxygen is $16$ and the relative atomic mass of carbon is $12$ (you can find these from the periodic table). Thus, we have $1$ carbon atom and $2$ oxygen atom so, $M_r = 12 + 2 \cdot 16 = \fbox{44}$

$\text{C}{O}_{2}$ is made of 2 oxygen atoms and 1 carbon atom.

The atomic mass of $\text{}(O = 16.00)$ and atomic mass of $\text{}(C = 12.01)$

$\text{C+O×2} , (16×2 = 32) + 12.01 {\approx} 44$