Hess's Law (Worksheet)
- Page ID
- 20062
\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)
\( \newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\)
( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\)
\( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)
\( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\)
\( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\)
\( \newcommand{\Span}{\mathrm{span}}\)
\( \newcommand{\id}{\mathrm{id}}\)
\( \newcommand{\Span}{\mathrm{span}}\)
\( \newcommand{\kernel}{\mathrm{null}\,}\)
\( \newcommand{\range}{\mathrm{range}\,}\)
\( \newcommand{\RealPart}{\mathrm{Re}}\)
\( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)
\( \newcommand{\Argument}{\mathrm{Arg}}\)
\( \newcommand{\norm}[1]{\| #1 \|}\)
\( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\)
\( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\AA}{\unicode[.8,0]{x212B}}\)
\( \newcommand{\vectorA}[1]{\vec{#1}} % arrow\)
\( \newcommand{\vectorAt}[1]{\vec{\text{#1}}} % arrow\)
\( \newcommand{\vectorB}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\( \newcommand{\vectorC}[1]{\textbf{#1}} \)
\( \newcommand{\vectorD}[1]{\overrightarrow{#1}} \)
\( \newcommand{\vectorDt}[1]{\overrightarrow{\text{#1}}} \)
\( \newcommand{\vectE}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash{\mathbf {#1}}}} \)
\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)
Name: ______________________________
Section: _____________________________
Student ID#:__________________________
Work in groups on these problems. You should try to answer the questions without referring to your textbook. If you get stuck, try asking another group for help.
Q1.
A 505 g piece of copper tubing is heated to 99.9°C and placed in an insulated vessel containing 59.8 g of water at 24.8°C. Assuming no loss of water and a heat capacity for the vessel of 10.0 J/K, what is the final temperature of the system?
Q2.
Calculate the \(\Delta{H_{rxn}}\) for
\[Ca_{(s)} + \frac{1}{2}O_2 + CO_2 \rightarrow CaCO_3 \nonumber \]
Given:
\[Ca + \frac{1}{2}O_2 \rightarrow CaO \;\;\;\;\; \Delta{H} = -635.1 \;kJ \nonumber \]
\[ CaCO_3 \rightarrow CaO + CO_2 \;\;\;\;\; \Delta{H} = 178.3\; kJ \nonumber \]
Q3.
Calculate \(\Delta{H_{rxn}}\) for:
\[2NOCl \rightarrow N_2 + O_2 + Cl_2 \nonumber \]
Given:
\[ \frac{1}{2}N_2 + \frac{1}{2}O_2 \rightarrow NO \;\;\;\;\; \Delta{H} = 90.3\; kJ \nonumber \]
\[ NO + \frac{1}{2}Cl_2 \rightarrow NOCl \;\;\;\;\; \Delta{H} = -38.6\; kJ \nonumber \]
Q4.
Calculate the \(\Delta{H_{rxn}}\) for the following reactions:
\(2H_2S_{(g)} + 3O_{2\;(g)} \rightarrow 2SO_{2\; (g)} + 2H_2O (g)\)
\(CH_{4\;(g)} + 4Cl_{2\;(g)} \rightarrow CCl_{4\;(l)} + 4HCl_{(g)}\)
\(SiO_{2\; (s)} + 4HF_{(g)} \rightarrow SiF_{4 (g)} + 2H_2O_{(l)}\)