diff --git a/Grade 9/Science/SNC1DZ/Study_Sheet.md b/Grade 9/Science/SNC1DZ/Study_Sheet.md
index 4bb7789..5825486 100644
--- a/Grade 9/Science/SNC1DZ/Study_Sheet.md	
+++ b/Grade 9/Science/SNC1DZ/Study_Sheet.md	
@@ -105,6 +105,41 @@
 <td>Chemical Change</td> 
 <td>A <b>change</b> in the starting substance and the <b>production of ONE or more new substances</b><br> Original substance does not disappear <b>BUT</b> the composition is rearranged</td>
 </tr>
+<tr>
+<td>Molecule</td>
+<td>Two or more <b>non-metal</b> atoms joined together</td>
+</tr>
+<tr>
+<td>Diatomic Molecules</td>
+<td>Molecules that <b>only</b> consists of 2 elements <br> `H O F BR I N CL` - `hyrodgen`, `oxygen`, `fluorine`, `bromine`, `iodine`, `nitrogen`, `chlorine`.</td>
+</tr>
+<tr>
+<td>Ions</td>
+<td>A Charged particle, that results from a <b>loss</b> (cation - positve, less electrons) or <b>gain</b> (anion - negative, more electrons) of electrons when bonding</td>
+</tr>
+<tr>
+<td>Electron</td>
+<td>Negatively Charged</td>
+</tr>
+<tr>
+<td>Proton</td>
+<td>Positively Charged</td>
+</tr>
+<tr>
+<td>Neutron</td>
+<td>Neutral Charged</td>
+</tr>
+<td>Ionic Charge</td>
+<td>The <b>sum</b> of the positive and negative charges in a ion</td>
+</tr>
+<tr>
+<td>Covalent Bond</td>
+<td>The sharing of electrons between atoms when bonding</td>
+</tr>
+<tr>
+<td>Valence Electrons</td>
+<td>Number of electrons on the most outer orbit/shell of the element</td>
+</tr>
 </table>
 
 ## Particle Theory of Matter
@@ -211,8 +246,37 @@
 ## Carbon
 
 ## Atoms
+- Subscripts - tells us how many of the atom are there, for example N<sub>2</sub> means there are 2 nitrongen atoms.
+- Use distrubutive property if there are brackets and a subscript, for example, (CO)<sub>2</sub> is equilivant to C<sub>2</sub>O<sub>2</sub>.
+- Atoms are stable if they have a full valence shell (noble gases)
+- Each family has the same amount of valence electrons as their family number, so `alkali metals` would have 1 valence electron, `alkaline earth metals` will have 2, `halogens will have` 7 and `noble gases` would have 8. 
+- They will also have the same amount of protons as their `atomic number`.
+- **Number of protons = Number of electrons**.
+- **Number of neutrons = mass - atomic number/number of protons**.
+
+
+## Bohr-Rutherford / Lewis-Dot Diagrams
+- **Bohr-Rutherford**
+    - Draw nucleus, and draw the apprioate number of orbits.
+    - Put number of **protons** and **neutrons** in the nucleus.
+    - Draw the correct number of electrons in each orbit
+     <img src="https://d2jmvrsizmvf4x.cloudfront.net/LHJtmeuTDVQ4l2uelrkw_imgres.png" width="300">
+
+- **Lewis-Dot Diagrams**
+    - Draw element symbol
+    - Put the right number of valence electrons around the symbol, perferably in pairs
+    <img src="https://qph.fs.quoracdn.net/main-qimg-a7b2f5ac4b313c27d4bac65c1c8f0a30.webp" width="300">    
+
+### Bonding
+- To combine 2 atoms, each element wants to be stable. So they each want a full valence shell, (outer shell) so they are stable.
+- They can either `gain`, `lose` or `share` electrons in order to become stable.
+- Example:
+    - Oxygen and Hydrogen, in order to become stable, they all need 8 valence electrons. Hydrogen has 1, oxygen has 6, so we bring in another hyrdogen and we let them share all their electrons, turning into H<sub>2</sub>O, or water.
+     <img src="https://www.seaturtlecamp.com/wp-content/uploads/2014/09/water-molecule-2.gif" width="300">
+
+- Use **arrows** to show gaining or losing electrons.
+- **Circle** to show sharing of electrons.
 
-## Bohr-Rutherford / Louis-Dot Diagrams
 
 
 ## Naming of Ionic Bonds