Question

A student adds 5.00 g of dry ice (solid `CO_2`) to an empty balloon. What will be the volume of the balloon at STP after all the dry ice sublimes (converts to gaseous `CO_2`)?

Answer 1

`V=2.56L`

Explanation:

Assuming that the `CO_2` gas is behaving ideally, therefore, we can use the ideal gas law to find the volume occupied by the gas in a ballon by:

`PV=nRT=>V=(nRT)/P`

At STP, the pressure is `P=1atm` and the temperature is `T=273K`.

To find the number of mole of `CO_2`, we can use the given mass as:

`n=m/(MM)`, where `MM=44g/(mol)` is the molar mass of `CO_2`.

`=>n=(5.00cancel(g))/(44cancel(g)/(mol))=0.114 mol`

Therefore, the volume is:
`=>V=(nRT)/P=(0.114cancel(mol)xx0.0821(L*cancel(atm))/(cancel(K)*cancel(mol))xx273cancel(K))/(1cancel(atm))=2.56L`