Chem 1.4B: Molar Mass and Percent Composition + 1.4C Empirical and Molecular Formulas!

this is short that I should just be study bio tbh. nvm I spoke too soon.

What is the definition of a Mole?

mass of a substance that contains as many particles as there are in 12g of carbon-12

What are the steps to get percent composition?

1. Find the total mass or molar mass of the compound

2. Divide each element by the compound and then multiply it by 100%

What is the definition of a Mole?

mass of a substance that contains as many particles as there are in 12g of carbon-12

What are the steps to get percent composition?

1. Find the total mass or molar mass of the compound

2. Divide each element by the compound and then multiply it by 100%

What does the empirical formula of a compound show?

the simplest ratio of a compound

What does the molecular formula of a compound show?

the actual number of each element in the compound

What are hydrates?

• a compound that contains a fixed ratio of water molecules within the crystalline structure of the compound

• This water of crystallization can be driven off by heating, resulting in an anhydrous salt

What is the Equation for Ideal Gases?

PV = nRT

• P = Pressure in kPa

• V = Volume in dm3

• n = Amount in mol

• T = Temperature in K

• R = 8.314 kPa dm3 mol-1 K-1

What is a Solution?

a homogenous mixture of at least two substances in one phase

What is a Solvent?

A substance that has other substances dissolved in it (does the dissolving)

What is a Solute?

Other substance present in a solution (gets dissolved)

What is a Dilute Solution?

a solution with a small quantity of solute dissolved per unit volume of solution

What is a Concentrated Solution?

Large quantity of solute dissolved per unit of solution

What is Concentration?

the ratio of the amount of a solute per volume of solution.

What is the Equation for Concentration?

Concentration = amount in mol / volume in dm³

What is dm³ equal to in litres?

1L