Stoichiometry

Question 1

What is stoichiometry?

Answer 1

the study of conversion for various chemistry molecules

Question 2

What are the conversion factors that we know?

Answer 2

1. mole - the commong units that can connect everything
2. molecular mass: when you are trying to go from grams to moles or moles to gram
3. Avocagro’s number : 1 mole = 6.022X10^23. This number can be used to convert mole to just about anything: atoms, molecules, particles, and fomula units
4. 1 mole= 22.4 L

Question 3

what are the three important steps to stoich?

Answer 3

1. Balance the equation
2. know what you are looking for
3. start the conversion tables until you get what is is you are looking for.

Question 4

what is the limiting reactant? and how to find it?

Answer 4

1. It is the reactant that will run out first within the reaction and therefore would give us the best

How to figure it?

1. Write a balance equation (to have the right moles)
2. Convert each reaction into it’s mole equivalent by using the moles/ moleculat mass ratio
3. Then divide the mole you found by the coefficient in the reaction
4. Compare the result and the smallest result will be the limiting reageant

Question 5

What is the theoretical yield?

Answer 5

• It is the outcome that we expect from the reaction if everything runs perfectly. However must time due to nature things do not necessarily run perfectly and you get the actual yield.

How to calculate it?

Question 6

What are some conversion factors for volume when you are not dealing with gas

Answer 6

1. Molarity: can be express as a mesurement of concentration where the equation is represented by Moles (solid) / per 1 liter
   
   1. ​If you want to use it as a conversion factor separate the solid part and the liquid part ( find the solid in mole and the liquid in Liter)
2. Density: can help you get the conversion of something in water
   
   1. Density: grams subtance/ per milli liters ( water H20 = 1g/ ml )

Solving the problems

1. write down the balance equation
2. write down what is given and what you are looking for
3. start your conversion equation with what you are not looking for
4. Know the conversion factors to get what you want

Question 7

What is the mass percentage

Answer 7

• It is a way to measure the concentration of a solid dissolve per unit of liquid in a 100 % solution ( mass of the solute and mass of the liquid)
• terms that are helpful: per “each”, cent “100” mass “ how to measure both the solution and the solute”. Think 2% milk 2 % of fat per

Equation

• Mass % = mass of solute/ total mass of solution (mass of both solute and solvent) all X 100%

Question 8

What is a way to simplefy the formula of a compound? And what compound cannot be made into the simplified formulas?

Answer 8

1. molecular formula: actual formula of the compound C6H12O6
2. Emperical: the smallest whole number for the formula of the compound. CH2

How to find it?

1. assume you have 100g of the solution
2. converts grams to moles of each compound
3. devided by the smallest whole number

What compounds cannot have an emperical formula

BrINClHOF - The atoms that cannot be by themselves in nature and they are usually gasses ( non-metals)

H2, N2, O2, F2, Cl2, B2, I2