Class Central is learner-supported. When you buy through links on our site, we may earn an affiliate commission.

Duke University

Introduction to Chemistry: Reactions and Ratios

Duke University via Coursera


This is an introductory course for students with limited background in chemistry; basic concepts involved in chemical reactions, stoichiometry, the periodic table, periodic trends, nomenclature, and chemical problem solving will be emphasized with the goal of preparing students for further study in chemistry as needed for many science, health, and policy professions.


  • Introduction
    • Over the seven weeks of Introduction to Chemistry: Reactions and Ratios, you will be able to progress from a most basic knowledge of matter and energy to solving interesting real world chemical reaction stoichiometry problems. Each lesson in the course introduces some new concepts that allow you to build upon the material from previous lessons, so completing the coursework in the order that it is delivered will be most beneficial for developing a thorough understanding of synthesized information. This course is intended for students with very little background in the subject, but a strong foundation in algebra is needed to solve some of the problems.In the first unit, the course will first introduce the basic concepts of scientific methods and measurement. Then we will talk about matter, energy, and stoichiometry. Last, we prepared several lab demonstrations by Dr. Ken Lyle. I hope that you are as excited as I am to this amazing world of chemistry! Good luck!
  • Matter and Energy
    • If you are interested in significant figures in more detail, here are some good videos to follow on Khan Academy.

      This week we will continue our explorations of matter and energy. We will discuss the sub-atomic particles that govern chemical reactions, isotopes, anions, and cations. We will learn how to name compounds, calculate formula masses, convert between grams and moles, examine periodic trends, and more! An advanced problems set is posted now; that is a longer assignment and is optional unless you would like to be eligible for the Honor’s Track. You can still earn a regular verified certificate without completing the advanced problem sets, so please be sure to keep working on the normal weekly exercises.

  • Compounds
    • In this week's videos and exercises (aka quizzes), we will learn how to name compounds, calculate formula masses, convert between grams and moles, examine periodic trends, and more!

      I hope you enjoyed the last two weeks of learning chemistry. Great work on watching videos, posting on the discussion forum and submitting your exercises!

  • Chemical Composition and Reactions
    • Week 4 for Introduction to Chemistry: Reactions and Ratios is about to begin! This week will be filled with introductions to chemical compositions, chemical reaction terminology, and reaction calculations.

      If any of the following questions interest you, then watching this week's videos and doing some practice problems are probably a good way to get started! How much sodium is in my diet? What amount of pollutants are in drinking water? How much iron is in iron ore for steel production? These of the types of problems you will be able to address this week.

  • Solutions and Solubility Rules
    • In the past five weeks of the course, we have learned concepts, rules, and skills, including but not limited to: the definitions of atoms, elements, molecules, and compounds; energy changes; Coulomb’s Law, molecular stoichiometry; atomic structures; periodic trends; the mole; compounds; atomic and molecular masses; molecular stoichiometry; balancing chemical equations.

      In this coming week, we will be discussing aqueous solutions, solubility rules, precipitations and electrolytes! We are also going to learn the first type of chemical reaction equation in this course: Dissolutions.

  • Acid-base and Redox Reactions
    • We are almost at the end of our course! I hope this has been a rewarding experience for you because I know that the course is not an easy one and it is relatively long. So kudos to everyone who has made it this far!

      Week 6 for Introduction to Chemistry: Reactions and Ratios will include very basic introductions to acid-base and redox reactions. We will also practice combining what we know from previous weeks to complete reaction calculations.

  • Final Exam
    • Congratulations on making through to the final week of the course! It was not an easy journey for the past six weeks with dozens of videos, exercises, problem sets, and forum discussions. Kudos to the many of you who completed the honors lessons on top of the other work. I am proud of all of you!

Taught by

Dorian Canelas


4.6 rating, based on 10 Class Central reviews

4.7 rating at Coursera based on 1195 ratings

Start your review of Introduction to Chemistry: Reactions and Ratios

  • I really enjoyed this course. The explanations were clear and concise and perfectly illustrated the presented concepts. I especially enjoyed the advanced problem sets which provided a deeper understanding of the material. Professor Canelas is a talented and caring instructor. Thank you!
  • José Diaz Seng
    This is a nice introduction to general chemistry. I certainly learned some chemical terminology, acquired stoichiometry skills, learned how to analyze solutions / solubility and got a deeper working knowledge of the periodic table. Professor Canelas…
  • Anonymous
    Hi everyone, this course is a great one and my reasons are these. Starting with the teacher, she is a very good based on the way she delivers those topics. she made them so simple to understand. That was what made take so much interest in the course. Not excluding those demonstrations, she made them so illustrative. The course widened my knowledge on those topics I already knew. It helped so much with my preparations for my final year exams in secondary school. This course is a very good one to take which I know if you try it, you will never regret.
  • Shabaz Khurshid Hassan
    Hi guys
    I am new in this course. As a chemical engineer i wanna to increase my knowledge and information and reactions of the science of a chemistry. I hope this course will help us and being a good course.
  • Very helpful to learn the students of primary class. By choosing this course
    We came to know about the physical and chemical change during reaction
  • Profile image for Harini S
    Harini S
    This course is simply amazing! Professor Canelas teaches really well. Perfect course for beginners. There are many questions and experiments. Highly recommend it.
  • Awilda
  • Mohamed Baymie Ibrahim Elmasry
  • Doaa Tarek Muhammad
  • Profile image for Denise Spiegel
    Denise Spiegel

Never Stop Learning.

Get personalized course recommendations, track subjects and courses with reminders, and more.

Someone learning on their laptop while sitting on the floor.