Update Unit_2_Chemistry_Study_Sheet.md

Grade 9/Science/SNC1DZ/Unit_2_Chemistry_Study_Sheet.md

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  |Qualitative Property|A property that is NOT measured and has **```no numerical value```**|Ex. **```Colour, odor, texture```**|
 
 ## Density
+- **The amount of mass (or matter) in a certain volume**
+- It is a **quantative** physical property
+- For any given substance, density is a **characteristic physical property**.
+
 <img src="https://mathsmadeeasy.co.uk/wp-content/uploads/2017/12/density-mass-volume-triangle.png" width="300">
 
+### Sinking Or Floating?
+- Most solids are **more** dense than liquids **(except water!)**
+- When you place a solid object inside a liquid
+    - It will **sink** if the object is **more** dense than the liquid
+    - It will **float** if the object is **less** dense than the liquid
+
+### Strange Behaviour of Water
+- Its clear, odourless, tasteless, freezes at O<sup>o</sup>C, boils at 100<sup>o</sup>C
+- `Its solid form floats on its liquid form!`
+    - `Water particles are different`
+    - Due to their `shape` and the way in which the `particles` are arranged, forces it to take up `more space` when packed.
+    - Its density is the highest at 4<sup>o</sup>C, where its in liquid form.
+
+### Graphs
+- To calculate the density on a graph, simply find the slope of any 2 points on the line in the graph
+
+<img src="http://www.chemistryland.com/CHM151Lab/Lab02Density/Graph.jpg" width="300">
+
 ## Quantitative physical Properties
  - **```Density```**: amount of ```stuff``` (or mass) per unit volume (g/cm<sup>3</sup>)
  - **```Freezing Point```**: point where water solidifies (0<sup>o</sup>C)