molecalculator

Section 08

Heat, energy and rate calculators

Heat absorbed or released from mass, specific heat and temperature change, and first-order rate laws: half-life, rate constant and the amount left after a time.

Calculators in this section
30
Typical formula
q = m × c × ΔT
Photo collage: a metal block and a glass thermometer beside a polystyrene cup calorimeter on a lab bench, and a close-up of a small metal cylinder on a heat-proof mat.

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Everything in Heat, Energy & Rates

PageWorks outExample result
Air Enthalpy Calculator: Moist-Air Energy ExplainedMoist-air enthalpy318.67 kJ/kg dry air
Change in Gibbs Free Energy: Formula and MeaningGibbs free energy change-24.907 kJ/mol
Enthalpy Calculation Formula and Worked ExampleMolar enthalpy change-57.20 kJ/mol
Enthalpy Calculation in Calorimetry: Formula and ExampleReaction enthalpy-41.84 kJ/mol
Enthalpy Calculation: Formula, Examples, and LimitsEnthalpy change10,000.00 J
Enthalpy Calculations for A-Level ChemistryHeat transferred2,090.00 J
Enthalpy Calculator From Dry-Bulb TemperatureMoist-air enthalpy50.31 kJ/kg dry air
Enthalpy of Formation Calculator and Hess’s LawReaction standard enthalpy change107.68 kJ/mol reaction
Equilibrium Constant Calculator: Calculate Kc
Feed Water Enthalpy Calculator and FormulaFeed water enthalpy104.50 kJ/kg
First Order Rate Constant: Formula and CalculatorFirst-order rate constant0.0058 s^-1
First-Order Half-Life Calculator: Amount Left After a TimeAmount left14.142 same unit as start
Gibbs Free Energy Calculator and FormulaGibbs free-energy change ΔG-24.907 kJ/mol
HVAC Enthalpy Calculator: Moist-Air Energy ExplainedHumidity ratio0.00986 kg water/kg dry air
Metal Specific Heat Calculator: Heat From q = mcΔTHeat absorbed (negative = released)4,933.5 J
Outdoor Air Enthalpy Calculator: HVAC Moist-Air ValuesMoist-air enthalpy50.26 kJ/kg dry air
Outside Air Enthalpy Calculator: HVAC Moist-Air EnergyOutside-air enthalpy71.17 kJ/kg dry air
Propane Enthalpy Calculator: Heat from Temperature ChangeEnthalpy change5.5200 kJ/mol
Psychrometric Enthalpy Calculator and FormulaMoist-air enthalpy318.67 kJ/kg dry air
R134a Pressure-Enthalpy Diagram CalculatorTemperature in kelvin283.15 K
Rate Constant Formula: Calculate k from Rate DataRate constant k0.1000 L/(mol·s)
Rate Constant Unit Formula and Reaction-Order GuideUnit scale relative to (mol/L)^(1−n)/s1.000000
Rate Constant Units: Find Them From the Rate LawRate constant unit factor1.000000 (mol/L)^(1-n)·time⁻¹
Rate Constant Units: Formula and Worked ExampleRate constant unit as concentration^(1-order) per second1 (mol/L)^(1-order)/s
Refrigerant Enthalpy Calculator: Formula and UsesEstimated enthalpy change from reference17.00 kJ/kg
Saturated Liquid Enthalpy Calculator and Formula
Saturated Steam Enthalpy Calculator and FormulaSaturated mixture specific enthalpy2,675.50 kJ/kg
Steam Enthalpy Calculator: Find Specific EnthalpySpecific enthalpy, approximate liquid-water estimate501.60 kJ/kg
Temperature to Enthalpy Calculator: What You NeedEnthalpy change (sensible heat)251.0 kJ
Water Enthalpy Calculator: Heat and Energy ChangeEnthalpy change251.04 kJ

Every calculator uses a standard formula and shows it, with the constants and unit factors it needs. Method and constants.