Cheat sheet for chemistry test Cheat Sheet by sparklyamelia

 When doing covalent formulas don't look at the ion charges
 Remember there are diatomic molecules, that chemical equation might not actually be balanced
 Don't rush through it
 Triple check everything

Double­-check everything

1. write the symbols in order
2. write in the elements ionic charge
3. drop the charges (+ and - sign)
4. criss-­cross the numbers and make them subscripts
5. reduce the subscr­ipts, if possible. Drop the number 1.

1. The name includes both elements in the formula
2. The name of the metallic element appears first
3. The non-me­tallic element appears second. It's ending changes to IDE
4. If the metallic element has more than one charge (multi­valent). Then a Roman numeral must be put in to identify which charge is present

1. know the formula
2. All the Bohr Diagram Ion rules apply
3. Draw the Ions side by side

1. Draw nucleus
2. Draw symbol, proton number, and neutron number in the nucleus
2. Draw electrons around the nucleus

1. Write the symbols and correct formulas to represent the reactants and products
2. You cannot change the formulas (cannot change the subscr­ipts)
3. Place coeffi­cients in front of the symbols and formulas to change the number of atoms
4. Work from the left to the right of the equation
5. When you are stuck, double up the first compound and solve it from there

1. use the prefixes to determine the subscript for each atoms
NEVER REDUCE THE SUBSCRIPTS

1.show touching valance shells

4. Add square brackets
5. Show ion charge (upper right)
 Positive ions always have empty valance shells
 Negative ions always have full valance shells

4. Add square brackets
5. Show ion charge (upper right)
 Positive ions always have empty valance shells
 Negative ions always have full valance shells

1. know the formula
2. all the Lewis diagram Ion rules apply
3. Draw the Ions side by side

1. symbol (repre­sents nucleus)
2. Draw valance shell electrons
 Empty or full
 positive ions-empty
 negative ions-full
3. square brackets
4. charge

1. Don't change to ending to IDE
2. In a formula, if the subscript following the symbols is 2 or more, you must put brackets around the polyatomic ion

1. Use prefixes to identify the number of atoms in a covalent compound
2. prefixes are found on the last page of the data sheet
3. Normally don't use mono on the first atom
4. IDE ending on the second atom

Make sure to check if it is Bohr's model or Lewis Diagram

1. Symbol (repre­sents the nucleus)
2. Only draw the valance shell electrons