nacl has a $delta h_{fus}=30.2 kj/mol$. what is the mass of a sample of nacl that needs 732.6 kj of heat to…

nacl has a $delta h_{fus}=30.2 kj/mol$. what is the mass of a sample of nacl that needs 732.6 kj of heat to melt completely? use $q = ndelta h$.\n24.3 g\n82.7 g\n1,407.1 g\n1,417.7 g

nacl has a $delta h_{fus}=30.2 kj/mol$. what is the mass of a sample of nacl that needs 732.6 kj of heat to melt completely? use $q = ndelta h$.\n24.3 g\n82.7 g\n1,407.1 g\n1,417.7 g

Answer

Explanation:

Step1: Calculate the number of moles

We know that $q = n\Delta H_{fus}$, where $q = 732.6\ kJ$ and $\Delta H_{fus}=30.2\ kJ/mol$. Rearranging for $n$, we get $n=\frac{q}{\Delta H_{fus}}$. $n=\frac{732.6\ kJ}{30.2\ kJ/mol}=24.26\ mol$

Step2: Calculate the molar - mass of NaCl

The molar - mass of $NaCl$ is $M = 22.99\ g/mol+35.45\ g/mol = 58.44\ g/mol$.

Step3: Calculate the mass of NaCl

Using the formula $m = nM$, where $n = 24.26\ mol$ and $M = 58.44\ g/mol$. $m=24.26\ mol\times58.44\ g/mol\approx1417.7\ g$

Answer:

1,417.7 g