Answer:
The mass of the surrounding is [tex]M_t = 263.9 \ g[/tex]
Explanation:
From the question we are told that
The mass of [tex]NaOH[/tex] is [tex]m = 13.9 \ g[/tex]
The mass of water is [tex]m_w = 250.0g[/tex]
The chemical equation for the dissociation process is
[tex]NaOH _{(s) } ---> Na^{+}_{(aq)} + OH^{-} _{(aq)}[/tex]
The specific heat capacity of the mixture is [tex]c_p = 4.18 J g^{-1} C^{-1}[/tex]
The combined mass of the solution is
[tex]M_t = 13 + 250[/tex]
[tex]M_t = 263.9 \ g[/tex]
The mass of the surround here is the mass of the coffee-cup calorimeter and this contain the mixture ( water and the NaOH ) so the mass of the surrounding is
[tex]M_t = 263.9 \ g[/tex]
