diff --git a/schemas/amountOfChemical.schema.tpl.json b/schemas/amountOfChemical.schema.tpl.json
index 98a905a..5f460b2 100644
--- a/schemas/amountOfChemical.schema.tpl.json
+++ b/schemas/amountOfChemical.schema.tpl.json
@@ -1,6 +1,7 @@
 {
   "_type": "chemicals:AmountOfChemical",
   "required": [
+    "amount",
     "chemicalProduct"
   ],
   "properties": {
diff --git a/version.txt b/version.txt
index 8c1384d..29ef827 100644
--- a/version.txt
+++ b/version.txt
@@ -1 +1 @@
-v2
+v3