Enthalpy Change Per Mole Calculator

The Enthalpy Change Per Mole Calculator helps determine the amount of heat absorbed or released during a 化学 reaction, standardized to one mole of a substance. This is an important concept in thermochemistry and is use to compare reactions on a per-mole basis. The calculator is part of the Thermodynamics and Chemistry Energy Analysis Calculator 类别。

This tool is essential for students, researchers, and lab technicians who want to analyze energy changes accurately and compare results across different reactions and substances.

Formula of Enthalpy Change Per Mole Calculator

ΔH (kJ/mol) = q / n

详细分类：

• ΔH = Enthalpy change per mole (in kilojoules per mole, kJ/mol)
• q = Heat released or absorbed during the process (in kilojoules, kJ)
• n = Number of moles of the substance involved (in mol)

How to Calculate Heat (q)

If heat is not directly given, calculate it using:

q=m×c×ΔT

地点：

• m = Mass of the substance or solution (in grams)
• c = 比热 capacity (in J/g·°C; for water, typically 4.18 J/g·°C)
• ΔT = Temperature change = Final temperature − Initial temperature (in °C)

Convert to kilojoules:
q (kJ) = q (J) / 1000

How to Calculate Moles (n)

You can calculate moles using either:

• n = Mass / 摩尔质量 (for solids or pure substances)
• N = 浓缩 × 体积 (for solutions; volume in liters)

快速参考表

Here’s a useful table of values for common reactions and situations:

q (kJ)	n (mol)	ΔH（千焦/摩尔）
2.10	0.050	42.00
3.75	0.100	37.50
1.25	0.025	50.00
0.95	0.020	47.50
5.00	0.200	25.00

This table helps estimate enthalpy change quickly when typical values are involve.

Example of Enthalpy Change Per Mole Calculator

Suppose you perform a reaction where 2.508 kJ of heat is release, and you know 0.050 mol of product was form.

第 1 步：使用公式

ΔH = q / n = 2.508 / 0.050 = 50.16 kJ/mol

If the heat is released, the reaction is exothermic, and you may show this as:

ΔH = −50.16 kJ/mol

So, each mole of product formed releases 50.16 kJ of energy.

最常见的常见问题解答