What is $w$ when $3\mathrm{.}95kg$ of $H_{2}O(l),$ initially at $25\mathrm{.}0C,$ is converted into water vapour at $121C$ against a constant external pressure of $1\mathrm{.}00$atm $?$ Assume that the vapour behaves ideally and that the density of liquid water is $1\mathrm{.}00\frac{g}{m}L.($Remember to include a $"+"$ or $"-"$ sign as appropriate.$)$

Enter your answer in acceptable SI units, accurate to $3$ significant figures. Use an acceptable SI symbol for units.