How do you know if a chemical equation is balanced? What can you change to balance an equation? Play a game to test your ideas!

This class surveys developmental entrepreneurship via case examples of both successful and failed businesses and generally grapples with deploying and diffusing products and services through entrepreneurial action. By drawing on live and historical cases, especially from South Asia, Africa, Latin America as well as Eastern Europe, China, and other developing regions, we seek to cover the broad spectrum of challenges and opportunities facing developmental entrepreneurs. Finally, we explore a range of established and emerging business models as well as new business opportunities enabled by developmental technologies developed in MIT labs and beyond.

I use this activity to reinforce student understanding for predicting products or making sense of their products.Before this activity students should understand multiplication expressions and/or equations.  Students should know that the first factor represents the number of groups, and the second factor represents the size of the group.  For instance, 5 x 3 means five groups of three, or taking 3, five whole times.  So with fractions, 2/5 x 3/4, is the same as 2/5 of 3/4, taking a fraction of a fraction, or a part of a part.Students should use their understanding of expressions and/or equations to help them make predictions about the product.  For instance, if they are taking a part of a part (fraction times a fraction) it makes sense that their product would be less than.  If multiplying by 2/2 or 1, they are taking the whole amount, and only the whole, so their product would be equal to.  Lastly, if they are multiplying by a number greater than a whole or one, then it makes sense that the product will be greater than.  The whole amount and more is being taken, so again a greater product is reasonable.

Create your own sandwich and then see how many sandwiches you can make with different amounts of ingredients. Do the same with chemical reactions. See how many products you can make with different amounts of reactants. Play a game to test your understanding of reactants, products and leftovers. Can you get a perfect score on each level?

Students investigate the endothermic reaction involving citric acid, sodium bicarbonate and water to produce carbon dioxide, water and sodium citrate. In the presence of water [H2O], citric acid [C6H8O7] and sodium bicarbonate [NaHCO3] (also known as baking soda) react to form sodium citrate [Na3C6H5O7], water [H2O], and carbon dioxide [CO2]. Students test a stoichiometric version of the reaction followed by testing various perturbations on the stoichiometric version in which each reactant (citric acid, sodium bicarbonate, and water) is strategically doubled or halved to create a matrix of the effect on the reaction. By analyzing the test matrix data, they determine the optimum quantities to use in their own production companies to minimize material cost and maximize CO2 production. They use their test data to "scale-up" the system from a quart-sized ziplock bag to a reaction tank equal to the volume of their classroom. They collect data on reaction temperature and CO2 production.