Quantities in Chemical Reactions

These flashcards cover key concepts from the lecture on chemical reactions, stoichiometry, limiting reactants, and enthalpy.

What is the purpose of a chemical equation in stoichiometry?

It provides a 'recipe' for how reactants combine to form products.

What is the term for the reactant that is completely consumed in a chemical reaction?

Limiting reactant (or limiting reagent).

How do you calculate the percent yield of a chemical reaction?

Percent yield = (actual yield / theoretical yield) × 100%.

If you have 3 cups of flour, 10 eggs, and 4 tsp of baking powder, which ingredient is the limiting reactant if 15 pancakes can be made with the flour?

Flour is the limiting reactant since it produces the least number of pancakes.

In the example of making pancakes with 2 eggs yielding 5 pancakes, how many pancakes can you make with 8 eggs?

20 pancakes.

What does the theoretical yield represent in a chemical reaction?

The amount of product that can be made based on the amount of limiting reactant.

What is enthalpy in the context of chemical reactions?

A measure of the heat evolved or absorbed in a reaction.

What signifies an exothermic reaction in terms of enthalpy?

Energy is released into the surroundings, resulting in a negative enthalpy of reaction.