diff --git a/schemas/chemicalMixture.schema.tpl.json b/schemas/chemicalMixture.schema.tpl.json
index 2d605c7..51c95b7 100644
--- a/schemas/chemicalMixture.schema.tpl.json
+++ b/schemas/chemicalMixture.schema.tpl.json
@@ -1,5 +1,8 @@
 {
   "_type": "chemicals:ChemicalMixture",
+  "_categories": [
+    "chemicalProduct"
+  ],
   "required": [
     "hasPart",
     "type"
diff --git a/schemas/chemicalSubstance.schema.tpl.json b/schemas/chemicalSubstance.schema.tpl.json
index 0a02095..dd6df46 100644
--- a/schemas/chemicalSubstance.schema.tpl.json
+++ b/schemas/chemicalSubstance.schema.tpl.json
@@ -1,5 +1,8 @@
 {
   "_type": "chemicals:ChemicalSubstance",
+  "_categories": [
+    "chemicalProduct"
+  ],
   "required": [
     "molecularEntity"
   ],