Stoichiometry

The Mole Concepts

100

What is the Mole Concept and how is it used in chemistry?

An amount unit similar to familiar units like pair, dozen, gross. It provides a specific measure of the number of atoms or molecules in a bulk sample of matter.

200

What is the definition of a mole and how is it used to measure substances in chemistry?

a unit of measurement that is the amount of a pure substance containing the same number of chemical units (atoms, molecules etc).

300

How does Avogadro's constant relate to the concept of a mole?

One mole of a substance is equal to 6.022 × 10²³ units of that substance.

400

How can you determine the number of atoms or molecules in a given amount of substance using Avogadro's number?

The number of atoms = the number of moles × Avogadro's number

500

Can you explain how Avogadro's law relates volume,temperature, pressure, and number of particles at the molecular level?

Under the same conditions of temperature and pressure, equal volumes of different gases contain an equal number of molecules

Stoichiometry Calculations

100

A combination of two or more substances that are not chemically combined. (Has no fixed ratio)

Mixture 

200

Of the same kind (same state...)

Homogenous 

300

different; dissimilar (different state...)

Heterogenous

400

Any substance that cannot be broken down into simpler substances

Elements 

500

two or more toms held together by covelent bonds 

Molecule 

Limiting Reactants

100

What is a limiting reactant in a chemical reaction?

The reactant that is consumed first and limits the amount of product(s) that can be obtained.

200

How do you determine the limiting reactant in a given reaction?

Dividing the number of moles of each reactant by its stoichiometric coefficient in the balanced chemical equation

300

In what ways can excess reactants affect the outcome of a reaction?

Push the equilibrium in the direction of the product

400

What statements are true about limiting reactant?

The limiting reactant in a reaction is the first reactant to be completely converted to products

500

Why are expensive reactants usually the limiting reagents in industrial chemical processes?

To avoid waste and minimize costs

Solutions

100

What would happen is you just breathed oxygen?

Death 

200

What is the solvent of air?

Nitrogen 

300

What matters most about a solution?

The entropy of the solution compared to the pure solvent

400

What is the mass percent of sugar in soda?

9.2%

500

How do gas molecules dissolve in each other?

Very easily