diff --git a/Grade 10/Science/SNC2DZ/Unit 1: Chemistry.md b/Grade 10/Science/SNC2DZ/Unit 1: Chemistry.md
index 9993afd..700e3c0 100644
--- a/Grade 10/Science/SNC2DZ/Unit 1: Chemistry.md	
+++ b/Grade 10/Science/SNC2DZ/Unit 1: Chemistry.md	
@@ -156,6 +156,11 @@ are all mono-valent. (not multi-valent)
 |Dihydrogen phosphate ion|$`H2PO_4^-`$|
 |Monohydrogen phosphate ion|$`HPO_4^{2-}`$|
 
+- For above, we use mono for phosphate to avoid ambigious cases, where $`H_2PO_4^{-}`$ and $`H_2PO_4^{2-}`$ are the same if we don't put `mono` infront. As for the Hyrogen carbonate ion
+we don't put a mono due to no ambigious cases. 
 
-
+## Molecular Compounds
+- Are not made of ions, instead molecules
+- Shared pairof electrons -> `covalent bonds`
+-