equations

**Moles, mass and formula mass**

moles = mass/mr

**Percentage yield**

* Percentage yield = (actual yield / theoretical yield) x 100

**calculating empirical formula from masses**

**Step 1**: Find the **moles** of each element using the equation **moles = mass / Mr.**

**Step 2**: **divide** each of the moles by the **smallest number (of moles)** calculated.

**Step 2**: **divide** each of the moles by the **smallest number** calculated.

what is the empirical formula

The **empirical formula** is the **simplest whole number ratio** of atoms of each element in a compound.

**Moles, concentration and volume**

moles = conc x volume

mass, concentration and volume

mass= conc x volume

**Molar volume of a gas**

volume of a gas (in dm^3) = moles x 24

1dm^3 in cm^3

1000

multiple for nano (n)

x10^-9

multiple for a micro(μ)

10^-6

multiple for a milli (m)

10^-3

multiple for a centi (c)

10^-2

multiple for a kilo (k)

10^3

multiple for a mega (M)

10^6

multiple for a Giga (G)

10^9

multiple for a tera (T)

10^12

how to find limiting reactant

1. find the moles of each reactant
2. find the molar ratio to a prodcut in the equation ( use the big numbers
3. find out how many moles each reactant will make of the product
4. therefore ------ is the limiting factor as it produces --- moles less than -----