Amount of substance | Physical constants

Molar mass constant

The molar mass constant, usually denoted by Mu, is a physical constant defined as one twelfth of the molar mass of carbon-12: Mu = M(12C)/12. The molar mass of any element or compound is its relative atomic mass (atomic weight) multiplied by the molar mass constant. The mole and the relative atomic mass were originally defined in the International System of Units (SI) in such a way that the constant was exactly 1 g/mol. That is, the numerical value of the molar mass of an element, in grams per mole of atoms, was equal to its atomic mass relative to the atomic mass constant, mu. Thus, for example the average atomic mass of chlorine is approximately 35.446 daltons, and the mass of one mole of chlorine atoms was approximately 35.446 grams. On 20 May 2019, the SI definition of mole changed in such a way that the molar mass constant is no longer exactly 1 g/mol. However, the difference is insignificant for all practical purposes. According to the SI, the value of Mu now depends on the mass of one atom of carbon-12, which must be determined experimentally. As of that date, the 2018 CODATA recommended value of Mu is 0.99999999965(30)×10−3 kg⋅mol−1. The molar mass constant is important in writing dimensionally correct equations. While one may informally say "the molar mass of an element M is the same as its atomic weight A", the atomic weight (relative atomic mass) A is a dimensionless quantity, whereas the molar mass M has the units of mass per mole. Formally, M is A times the molar mass constant Mu. (Wikipedia).

Video thumbnail

Molar Mass Calculations

This video shows you how to calculate the molar mass for several compounds using their chemical formulas. You can see a listing of all my videos at my website, http://www.stepbystepscience.com

From playlist Chemistry Videos

Video thumbnail

How To Calculate The Molar Mass of a Compound - Quick & Easy!

This chemistry video tutorial explains how to calculate the molar mass of a compound. It contains plenty of examples and practice problems. General Chemistry 1 Review: https://bit.ly/3DNmZqb PDF Worksheet - 160 Questions: https://bit.ly/37SVLn6 New Chemistry Video Playlist: https://ww

From playlist New AP & General Chemistry Video Playlist

Video thumbnail

Molar Volume Calculated Two Different Ways

Mr. Swarthout shows you two ways to calculate the volume of one mole of a gas at standard temperature and pressure. You can see a listing of all my videos at my website, http://www.stepbystepscience.com

From playlist Chemistry Videos

Video thumbnail

Chemistry - Atoms, Molecules, and Ions (5 of 23) Molar Mass

Visit http://ilectureonline.com for more math and science lectures! In this video I will explain and gives examples of what is a molar mass.

From playlist Michel van Biezen: CHEM - Introduction

Video thumbnail

Molar Mass | U1 | ATAR Chemistry QCE

ATAR Chemistry for the QCE Y11 U1 T3 Chemical Reactions - Molar Mass How to work out molar mass (M)

From playlist Topic 1 Stoichiometry - at a slower pace...

Video thumbnail

Molar Mass

Watch more videos on http://www.brightstorm.com/science/chemistry SUBSCRIBE FOR All OUR VIDEOS! https://www.youtube.com/subscription_center?add_user=brightstorm2 VISIT BRIGHTSTORM.com FOR TONS OF VIDEO TUTORIALS AND OTHER FEATURES! http://www.brightstorm.com/ LET'S CONNECT! Facebook ► h

From playlist Chemistry

Video thumbnail

Lecture 24

Chemistry 1B Professor Eric Potma Department of Chemistry University of California, Irvine

From playlist Chem 1P: Studio Version

Video thumbnail

Molar Volume

Shows you how to calculate that the volume of one mole of an ideal gas at standard temperature and pressure is equal to 22.4 liters. You can see a listing of all my videos at my website, http://www.stepbystepscience.com

From playlist Chemistry Videos

Video thumbnail

Chemistry - Solutions (13 of 53) Expressing Concentrations: Molality

Visit http://ilectureonline.com for more math and science lectures! In this video I will find the molality of a 40% (W/W) solution or ethanol and water.

From playlist CHEMISTRY 19 SOLUTIONS

Video thumbnail

Gas Law Problems Combined & Ideal - Density, Molar Mass, Mole Fraction, Partial Pressure, Effusion

This chemistry video tutorial explains how to solve combined gas law and ideal gas law problems. It covers topics such as gas density, molar mass, mole fraction, dalton's law of partial pressure, and graham's law of effusion. This video contains plenty of examples and practice problems.

From playlist New AP & General Chemistry Video Playlist

Video thumbnail

Thermodynamics 2b - Ideal Gases II

We continue our discussion of ideal gases. Here we derive the Ideal Gas Law and the heat capacity of an ideal monatomic gas.

From playlist Thermodynamics

Video thumbnail

Stoichiometry Part 3 - Gases and Liquids

IB Chemistry Lesson on the stoichiometry of gases and liquids.

From playlist IB Chemistry

Video thumbnail

Molar Heat Capacities of Gases, Equipartition of Energy & Degrees of Freedom

This physics video tutorial explains how to calculate the molar heat capacity of a monoatomic gas and a diatomic gas. it gives a simple formula to achieve this. In addition, it discusses the equipartition of energy principle as it relates to the average translational kinetic energy for e

From playlist New Physics Video Playlist

Video thumbnail

A Level Chemistry Revision "Calculating the Amount of Substance from Mass"

In this video, we start exploring how to calculate the amount of a substance in moles. First we look at what is meant by the amount of substance in terms of carbon-12 and what is meant by the Avogadro constant. We then look at how to work out the molar mass for an element, a molecule and a

From playlist A Level Chemistry Calculations Involving the Mole

Video thumbnail

🔴 LIVE CHEMISTRY TUTORING: Bring Your Chemistry Questions

Got Chemistry Questions? Don't worry I got answers for you! Whether it's explaining limiting reactants, showing you how to do stoichiometry problems or just how to draw lewis structures. Bring your questions and we'll pass Chemistry together this semester! 📗 FREE CHEMISTRY SURVIVAL GUIDE

From playlist LIVE Chemistry Q&A Spring 2018

Video thumbnail

General Chemistry 1 Review Study Guide - IB, AP, & College Chem Final Exam

This video tutorial study guide review is for students who are taking their first semester of college general chemistry, IB, or AP Chemistry. Even if you’re studying for the general chemistry section of the MCAT, DAT, PCAT, OAT or SAT Subject chemistry test, this video can help give you a

From playlist New AP & General Chemistry Video Playlist

Video thumbnail

Chemical Formulae, equations and calculations

IGCSE Edexcel Chemistry lessons on chemical calculations and stoichiometry

From playlist Edexcel IGCSE Chemistry

Video thumbnail

Quantum Numbers, The Electromagnetic Spectrum, Empirical & Molecular Formulas and Precipitation

In this LIVE I answer all the questions I received on quantum numbers, the electromagnetic spectrum, empirical and molecular formulas, net ionic equations, solubility and precipitation reactions! 📗 FREE CHEMISTRY SURVIVAL GUIDE https://melissa.help/freechemguide 👉 SHOP MY CHEMISTRY RESO

From playlist #AskMelissaMaribel Fall 2018

Video thumbnail

Chemistry: Molar Mass - with 5 examples | Homework Tutor

Chemistry Lessons: Molar Mass - with 5 examples Finding the molar mass of a compound is often the first step in more complicated chemistry problems. When we say "molar mass," we mean the mass of 1 mole of that compound. Sometimes it's called the Gram molecular mass . We'll also explain wh

From playlist Chemistry Lessons

Video thumbnail

Faraday's Law, How to Find the Molar Mass of an Acid, Net Ionic Equations

📗 FREE CHEMISTRY SURVIVAL GUIDE https://melissa.help/freechemguide 👉 SHOP MY CHEMISTRY RESOURCES 👈 https://melissamaribel.com/ -Naming Compounds Flashcards https://melissa.help/namingflashcards -Thermochemistry Notes https://melissa.help/thermonotes -Acids and Bases Notes https://melissa

From playlist General Chemistry 2: What You Need to Know

Related pages

Dalton (unit) | Relative atomic mass | Dimensional analysis | Physical constant | Avogadro constant | Speed of light