# How much energy is needed to vaporize 5.00 g of water?

Jun 29, 2017

We need the enthalpy of vaporization of water.......

#### Explanation:

For the reaction.......

${H}_{2} O \left(l\right) + \Delta \rightarrow {H}_{2} O \left(g\right)$

WHERE BOTH PRODUCT AND REACTANT ARE AT $100$ ""^@C,
..........

$\Delta {H}_{\text{vaporization}}^{\circ} = 40.66 \cdot k J \cdot m o {l}^{-} 1$

And thus we need to assess the molar quantity of the water vaporized......

$\Delta {H}_{\text{rxn}} = \frac{5.00 \cdot g}{18.01 \cdot g \cdot m o {l}^{-} 1} \times 40.66 \cdot k J \cdot m o {l}^{-} 1 = 11.3 \cdot k J$.