diff --git a/Grade 10/Science/SNC2DZ/Unit 1: Chemistry.md b/Grade 10/Science/SNC2DZ/Unit 1: Chemistry.md
index 54af3e2..9b2e2ac 100644
--- a/Grade 10/Science/SNC2DZ/Unit 1: Chemistry.md	
+++ b/Grade 10/Science/SNC2DZ/Unit 1: Chemistry.md	
@@ -204,13 +204,6 @@
 |Dichromate|$`Cr_2O_7^{2-}`$|
 |Sulfate|$`SO_4^{2-}`$|
 |Phosphate|$`PO_4^{3-}`$|
-|Hydronium|$`H_3O^+`$|
-|Cyanate|$`OCN^-`$|
-|Thiocyanate|$`SCN^-`$|
-|Iodate|$`IO_3^-`$|
-|Oxalate|$`C_2O_4^{2-}`$|
-|Silicate|$`SiO_3^{2-}`$|
-|Arsenate|$`AsO_4^{3-}`$|
 
 ### Oxyanions
 - Nitrate