Chemistry Unit 3: Stoichiometry Flashcards

Questions and Answers

What is the first step when approaching a BCA table problem?

Balancing equation.

What is the only measurement that can be used in a BCA table?

Moles, if in grams you must convert.

In the 'B' Row of a BCA table, what should the product(s) look like?

Why is the B Row equal to 0 for products?

The chemical reaction has not yet occurred, meaning that no product has been formed. Signup and view all the answers

What is a limiting reactant?

The substance that is totally consumed when the chemical reaction is complete/runs out first. Signup and view all the answers

What is an excess reactant?

The substance that is not used up completely in a reaction/the reaction that has leftovers. Signup and view all the answers

What is theoretical yield?

The mass of the product that should be formed in a chemical reaction. Signup and view all the answers

What is the actual yield?

The amount of product actually produced by a chemical reaction. Signup and view all the answers

What is percentage yield?

A way of seeing how close we are (theoretical) to the actual yield (what really happens). Signup and view all the answers

How do we find the percent yield?

Theoretical Yield/Actual Yield x 100 Signup and view all the answers

What does BCA tell us compared to Lab results?

BCA tells us theoretical yield; Lab tells us actual yield. Signup and view all the answers

Study Notes

BCA Tables and Mole Ratios

The first step in solving a BCA (Before, Change, After) table problem is to balance the chemical equation.
Measurements used in a BCA table must be in moles; if provided in grams, conversion is necessary.
In the "B" Row of a BCA table, product amounts are represented as 0, indicating no formation of products yet.
The reason products show 0 in the "B" Row is that the chemical reaction has not yet occurred.
A limiting reactant is the substance that is fully consumed when a reaction is complete, defining the extent of the reaction.
An excess reactant refers to the substance that remains unconsumed in a reaction, meaning there are leftovers post-reaction.
Theoretical yield represents the calculated mass of a product that should be formed based on stoichiometric calculations in a chemical reaction.
Actual yield is the mass of the product that is actually produced in a chemical reaction, obtained from experimental results.
Percentage yield provides a comparison of the theoretical yield to the actual yield, showing efficiency of the reaction.
To calculate percent yield, use the formula: (Theoretical Yield / Actual Yield) x 100.
BCA calculations provide insight into theoretical yield, while laboratory experiments yield actual yield results.

Description

This quiz focuses on understanding stoichiometry through BCA tables and mole ratios. Review key concepts like balancing equations and the importance of moles in calculations. Perfect for students preparing for chemistry exams.