LearnChemE

.elementor-515 .elementor-element.elementor-element-4354ca8 > .elementor-container > .elementor-column > .elementor-widget-wrap{align-content:flex-start;align-items:flex-start;}.elementor-515 .elementor-element.elementor-element-4354ca8{transition:background 0.3s, border 0.3s, border-radius 0.3s, box-shadow 0.3s;margin-top:0px;margin-bottom:0px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-4354ca8 > .elementor-background-overlay{transition:background 0.3s, border-radius 0.3s, opacity 0.3s;}.elementor-515 .elementor-element.elementor-element-18adb6d > .elementor-element-populated{transition:background 0.3s, border 0.3s, border-radius 0.3s, box-shadow 0.3s;margin:3px 0px 0px 0px;--e-column-margin-right:0px;--e-column-margin-left:0px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-18adb6d > .elementor-element-populated > .elementor-background-overlay{transition:background 0.3s, border-radius 0.3s, opacity 0.3s;}.elementor-515 .elementor-element.elementor-element-79bb1c4{transition:background 0.3s, border 0.3s, border-radius 0.3s, box-shadow 0.3s;margin-top:0px;margin-bottom:0px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-79bb1c4 > .elementor-background-overlay{transition:background 0.3s, border-radius 0.3s, opacity 0.3s;}.elementor-bc-flex-widget .elementor-515 .elementor-element.elementor-element-cf8bb55.elementor-column .elementor-widget-wrap{align-items:center;}.elementor-515 .elementor-element.elementor-element-cf8bb55.elementor-column.elementor-element[data-element_type="column"] > .elementor-widget-wrap.elementor-element-populated{align-content:center;align-items:center;}.elementor-515 .elementor-element.elementor-element-cf8bb55 > .elementor-widget-wrap > .elementor-widget:not(.elementor-widget__width-auto):not(.elementor-widget__width-initial):not(:last-child):not(.elementor-absolute){margin-bottom:0px;}.elementor-515 .elementor-element.elementor-element-cf8bb55 > .elementor-element-populated{margin:0px 0px 0px 10px;--e-column-margin-right:0px;--e-column-margin-left:10px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-071cb4c .hfe-heading-text{color:var( --e-global-color-primary );}.elementor-515 .elementor-element.elementor-element-071cb4c .hfe-icon i{color:var( --e-global-color-primary );}.elementor-515 .elementor-element.elementor-element-071cb4c .hfe-icon svg{fill:var( --e-global-color-primary );}.elementor-bc-flex-widget .elementor-515 .elementor-element.elementor-element-5ff9494.elementor-column .elementor-widget-wrap{align-items:center;}.elementor-515 .elementor-element.elementor-element-5ff9494.elementor-column.elementor-element[data-element_type="column"] > .elementor-widget-wrap.elementor-element-populated{align-content:center;align-items:center;}.elementor-515 .elementor-element.elementor-element-5ff9494 > .elementor-element-populated{margin:0px 0px 0px 0px;--e-column-margin-right:0px;--e-column-margin-left:0px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-99e6049 img{width:50px;max-width:50px;}.elementor-bc-flex-widget .elementor-515 .elementor-element.elementor-element-e3a08fe.elementor-column .elementor-widget-wrap{align-items:center;}.elementor-515 .elementor-element.elementor-element-e3a08fe.elementor-column.elementor-element[data-element_type="column"] > .elementor-widget-wrap.elementor-element-populated{align-content:center;align-items:center;}.elementor-515 .elementor-element.elementor-element-e3a08fe > .elementor-element-populated{margin:0px 0px 0px 0px;--e-column-margin-right:0px;--e-column-margin-left:0px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-773020b{text-align:center;}.elementor-515 .elementor-element.elementor-element-773020b img{width:40px;max-width:40px;}.elementor-bc-flex-widget .elementor-515 .elementor-element.elementor-element-6bb885c.elementor-column .elementor-widget-wrap{align-items:center;}.elementor-515 .elementor-element.elementor-element-6bb885c.elementor-column.elementor-element[data-element_type="column"] > .elementor-widget-wrap.elementor-element-populated{align-content:center;align-items:center;}.elementor-515 .elementor-element.elementor-element-6bb885c > .elementor-element-populated{margin:0px 0px 0px 0px;--e-column-margin-right:0px;--e-column-margin-left:0px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-544e1a8 img{width:100%;max-width:45px;}.elementor-bc-flex-widget .elementor-515 .elementor-element.elementor-element-8907359.elementor-column .elementor-widget-wrap{align-items:center;}.elementor-515 .elementor-element.elementor-element-8907359.elementor-column.elementor-element[data-element_type="column"] > .elementor-widget-wrap.elementor-element-populated{align-content:center;align-items:center;}.elementor-515 .elementor-element.elementor-element-8907359 > .elementor-element-populated{margin:0px 0px 0px 0px;--e-column-margin-right:0px;--e-column-margin-left:0px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-ef0a165{text-align:center;}.elementor-515 .elementor-element.elementor-element-ef0a165 img{width:100%;max-width:55px;}.elementor-bc-flex-widget .elementor-515 .elementor-element.elementor-element-2acf5d2.elementor-column .elementor-widget-wrap{align-items:center;}.elementor-515 .elementor-element.elementor-element-2acf5d2.elementor-column.elementor-element[data-element_type="column"] > .elementor-widget-wrap.elementor-element-populated{align-content:center;align-items:center;}.elementor-515 .elementor-element.elementor-element-2acf5d2.elementor-column > .elementor-widget-wrap{justify-content:flex-end;}.elementor-515 .elementor-element.elementor-element-2acf5d2 > .elementor-element-populated{margin:0px 0px 0px 0px;--e-column-margin-right:0px;--e-column-margin-left:0px;padding:0px 0px 0px 08px;}.elementor-515 .elementor-element.elementor-element-5a21732{text-align:left;}.elementor-515 .elementor-element.elementor-element-5a21732 img{width:100%;max-width:350px;}.elementor-515 .elementor-element.elementor-element-54633e8 > .elementor-container{min-height:0px;}.elementor-515 .elementor-element.elementor-element-54633e8{transition:background 0.3s, border 0.3s, border-radius 0.3s, box-shadow 0.3s;margin-top:0px;margin-bottom:0px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-54633e8 > .elementor-background-overlay{transition:background 0.3s, border-radius 0.3s, opacity 0.3s;}.elementor-515 .elementor-element.elementor-element-ff739e6 > .elementor-element-populated{margin:0px 0px 0px 0px;--e-column-margin-right:0px;--e-column-margin-left:0px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .hfe-nav-menu__toggle{margin:0 auto;}.elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item a.hfe-menu-item{padding-left:12px;padding-right:12px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item a.hfe-sub-menu-item{padding-left:calc( 12px + 20px );padding-right:12px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .hfe-nav-menu__layout-vertical .menu-item ul ul a.hfe-sub-menu-item{padding-left:calc( 12px + 40px );padding-right:12px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .hfe-nav-menu__layout-vertical .menu-item ul ul ul a.hfe-sub-menu-item{padding-left:calc( 12px + 60px );padding-right:12px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .hfe-nav-menu__layout-vertical .menu-item ul ul ul ul a.hfe-sub-menu-item{padding-left:calc( 12px + 80px );padding-right:12px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item a.hfe-sub-menu-item{padding-top:15px;padding-bottom:15px;}.elementor-515 .elementor-element.elementor-element-5b5f33e a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e a.hfe-sub-menu-item{font-size:1rem;}.elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e .sub-menu a.hfe-sub-menu-item{color:var( --e-global-color-primary );}.elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item a.hfe-menu-item:hover, .elementor-515 .elementor-element.elementor-element-5b5f33e .sub-menu a.hfe-sub-menu-item:hover, .elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item.current-menu-item a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item a.hfe-menu-item.highlighted, .elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item a.hfe-menu-item:focus{color:#CFB87C;}.elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item.current-menu-item a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item.current-menu-ancestor a.hfe-menu-item{color:#0377BD;}.elementor-515 .elementor-element.elementor-element-5b5f33e .sub-menu, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown .menu-item a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown .menu-item a.hfe-sub-menu-item{background-color:#fff;} .elementor-515 .elementor-element.elementor-element-5b5f33e .sub-menu li a.hfe-sub-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown li a.hfe-sub-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown li a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible li a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible li a.hfe-sub-menu-item{font-size:0.9rem;}.elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-nav-menu__layout-horizontal .sub-menu, .elementor-515 .elementor-element.elementor-element-5b5f33e nav:not(.hfe-nav-menu__layout-horizontal) .sub-menu.sub-menu-open, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown .hfe-nav-menu, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible .hfe-nav-menu{border-style:solid;border-width:1px 1px 1px 1px;border-color:#C4C4C4;}.elementor-515 .elementor-element.elementor-element-5b5f33e .sub-menu{border-radius:2px 2px 2px 2px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .sub-menu li.menu-item:first-child{border-top-left-radius:2px;border-top-right-radius:2px;overflow:hidden;}.elementor-515 .elementor-element.elementor-element-5b5f33e .sub-menu li.menu-item:last-child{border-bottom-right-radius:2px;border-bottom-left-radius:2px;overflow:hidden;}.elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown{border-radius:2px 2px 2px 2px;}.elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown li.menu-item:first-child{border-top-left-radius:2px;border-top-right-radius:2px;overflow:hidden;}.elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown li.menu-item:last-child{border-bottom-right-radius:2px;border-bottom-left-radius:2px;overflow:hidden;}.elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible{border-radius:2px 2px 2px 2px;}.elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible li.menu-item:first-child{border-top-left-radius:2px;border-top-right-radius:2px;overflow:hidden;}.elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible li.menu-item:last-child{border-bottom-right-radius:2px;border-bottom-left-radius:2px;overflow:hidden;}.elementor-515 .elementor-element.elementor-element-5b5f33e ul.sub-menu{width:262px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .sub-menu li a.hfe-sub-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown li a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible li a.hfe-menu-item{padding-left:8px;padding-right:8px;}.elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible a.hfe-sub-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown li a.hfe-sub-menu-item{padding-left:calc( 8px + 20px );padding-right:8px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .hfe-dropdown .menu-item ul ul a.hfe-sub-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e .hfe-dropdown-expandible .menu-item ul ul a.hfe-sub-menu-item{padding-left:calc( 8px + 40px );padding-right:8px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .hfe-dropdown .menu-item ul ul ul a.hfe-sub-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e .hfe-dropdown-expandible .menu-item ul ul ul a.hfe-sub-menu-item{padding-left:calc( 8px + 60px );padding-right:8px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .hfe-dropdown .menu-item ul ul ul ul a.hfe-sub-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e .hfe-dropdown-expandible .menu-item ul ul ul ul a.hfe-sub-menu-item{padding-left:calc( 8px + 80px );padding-right:8px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .sub-menu a.hfe-sub-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown li a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown li a.hfe-sub-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible li a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible li a.hfe-sub-menu-item{padding-top:8px;padding-bottom:8px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .sub-menu li.menu-item:not(:last-child), .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown li.menu-item:not(:last-child), .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible li.menu-item:not(:last-child){border-bottom-style:solid;border-bottom-color:#c4c4c4;border-bottom-width:1px;}.elementor-515 .elementor-element.elementor-element-6badb1b{margin-top:0px;margin-bottom:0px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-954b0da > .elementor-widget-wrap > .elementor-widget:not(.elementor-widget__width-auto):not(.elementor-widget__width-initial):not(:last-child):not(.elementor-absolute){margin-bottom:0px;}.elementor-515 .elementor-element.elementor-element-954b0da > .elementor-element-populated{margin:0px 0px 0px 0px;--e-column-margin-right:0px;--e-column-margin-left:0px;padding:0px 0px 0px 0px;}.elementor-515 .elementor-element.elementor-element-15d435d > .elementor-widget-container{margin:0px 0px 0px 0px;padding:0px 0px 0px 0px;}@media(max-width:1024px){.elementor-515 .elementor-element.elementor-element-071cb4c .hfe-heading{text-align:left;}.elementor-515 .elementor-element.elementor-element-99e6049 img{max-width:45px;}.elementor-515 .elementor-element.elementor-element-773020b img{max-width:45px;}.elementor-515 .elementor-element.elementor-element-544e1a8 img{max-width:45px;}.elementor-515 .elementor-element.elementor-element-ef0a165 img{max-width:56px;}.elementor-bc-flex-widget .elementor-515 .elementor-element.elementor-element-2acf5d2.elementor-column .elementor-widget-wrap{align-items:center;}.elementor-515 .elementor-element.elementor-element-2acf5d2.elementor-column.elementor-element[data-element_type="column"] > .elementor-widget-wrap.elementor-element-populated{align-content:center;align-items:center;}.elementor-515 .elementor-element.elementor-element-54633e8 > .elementor-container{min-height:0px;}.elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e .menu-item a.hfe-sub-menu-item{padding-top:5px;padding-bottom:5px;}.elementor-515 .elementor-element.elementor-element-5b5f33e a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e a.hfe-sub-menu-item{font-size:0.95rem;}.elementor-515 .elementor-element.elementor-element-5b5f33e .sub-menu a.hfe-sub-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown li a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown li a.hfe-sub-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible li a.hfe-menu-item, .elementor-515 .elementor-element.elementor-element-5b5f33e nav.hfe-dropdown-expandible li a.hfe-sub-menu-item{padding-top:8px;padding-bottom:8px;}}@media(min-width:768px){.elementor-515 .elementor-element.elementor-element-cf8bb55{width:36%;}.elementor-515 .elementor-element.elementor-element-5ff9494{width:7%;}.elementor-515 .elementor-element.elementor-element-e3a08fe{width:7%;}.elementor-515 .elementor-element.elementor-element-6bb885c{width:7%;}.elementor-515 .elementor-element.elementor-element-8907359{width:7.33%;}.elementor-515 .elementor-element.elementor-element-2acf5d2{width:35%;}}@media(max-width:1024px) and (min-width:768px){.elementor-515 .elementor-element.elementor-element-cf8bb55{width:38%;}.elementor-515 .elementor-element.elementor-element-5ff9494{width:6%;}.elementor-515 .elementor-element.elementor-element-e3a08fe{width:7%;}.elementor-515 .elementor-element.elementor-element-6bb885c{width:7%;}.elementor-515 .elementor-element.elementor-element-8907359{width:9%;}.elementor-515 .elementor-element.elementor-element-2acf5d2{width:33%;}}@media(max-width:767px){.elementor-515 .elementor-element.elementor-element-cf8bb55{width:100%;}.elementor-515 .elementor-element.elementor-element-071cb4c .elementor-heading-title, .elementor-515 .elementor-element.elementor-element-071cb4c .hfe-heading a{font-size:2rem;}.elementor-515 .elementor-element.elementor-element-5ff9494{width:3%;}.elementor-515 .elementor-element.elementor-element-e3a08fe{width:3%;}.elementor-515 .elementor-element.elementor-element-6bb885c{width:3%;}.elementor-515 .elementor-element.elementor-element-8907359{width:3%;}.elementor-515 .elementor-element.elementor-element-2acf5d2{width:100%;}.elementor-515 .elementor-element.elementor-element-2acf5d2 > .elementor-element-populated{padding:5px 5px 5px 5px;}.elementor-515 .elementor-element.elementor-element-5a21732 img{max-width:237px;}.elementor-515 .elementor-element.elementor-element-54633e8 > .elementor-container{min-height:50px;}.elementor-515 .elementor-element.elementor-element-5b5f33e > .elementor-widget-container{margin:0px 0px 0px 0px;padding:0px 0px 0px 0px;}}

Heats of Reaction: Screencasts

Explains how to determine heats of reaction at 298 K from heats of formation and how to calculate heats of reaction at elevated temperatures.

We suggest that after watching this screencast, you list the important points as a way to increase retention.

Explains Hess’s law and provides an example of how to use it to solve for the heat of reaction for an equation.

We suggest that after watching this screencast, you list the important points as a way to increase retention.

Uses Hess’s law to show how heat of combustion is used to calculate the heat of reaction. 

We suggest that after watching this screencast, you list the important points as a way to increase retention.

 

Important Equations:

\[\Delta H_{rxn} = \sum \nu_i \Delta H_{f,i} \]

where \(\Delta H_{rxn} =\) heat of reaction at 298 K, \(\nu_i = \) stoichiometric coefficient for component \(i\), and \(\Delta H_{f,i} = \) heat of formation (enthalpy of formation) or species \(i\) at 298 K.

\[ \Delta H_{reaction,T} = \Delta H_{reaction,298} + \int^{T}_{298} \Delta C_P\,dT \]

Heat capacity (J/(mol K)) can be of the form

\[C_{P,i} = A_i + B_iT + C_iT^2 + D_iT^3\]

where \(C_{P,i}\) is the heat capacity of component \(i\), \( A_i, B_i, C_i, \,and\, D_i\) are the constants for the heat capacity equation for component \(i\), and \(T\) is temperature in Kelvin.

\[\Delta C_P = \sum \nu_i C_{P,i} \]

\[\Delta H_{reaction,T} = \Delta H_{reaction,298} + \sum \nu_i A_i (T-298 + \frac{\sum \nu_i B_i}{2}(T^2-298) + \frac{\sum \nu_i C_i}{3}(T^3 -298^3) +\frac{\sum \nu_i D_i}{4}(T^4-298)\]

\[ \Delta H_{reaction,T} = \Delta H_{C,reactant}^{\circ} – \sum \Delta H_{C,product}^{\circ}\]

where \(\Delta H_{C,reactant}^{\circ} \) is the heat of combustion of a reactant at standard states, and \(\Delta H_{C,product}^{\circ} \) is the heat of combustion of a product at standard states.