Update Unit 1: Chemistry.md

Grade 10/Science/SNC2DZ/Unit 1: Chemistry.md

@@ -204,6 +204,13 @@
 |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
@@ -240,6 +247,8 @@
 |Hydrogen carbonate ion|$`HCO_3`$|
 |Dihydrogen phosphate ion|$`H2PO_4^-`$|
 |Monohydrogen phosphate ion|$`HPO_4^{2-}`$|
+|Hydrogen Sulfate|$`HSO_4^-`$|
+|Hydrogen Carbonate|$`HCO_3^-`$|
 
 - 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.