diff --git a/cal/trans.py b/cal/trans.py
index 8eab4e9de7654422aa5871670a2cf66573b5c305..463ab261b51b629738553b5137eb94df033be989 100644
--- a/cal/trans.py
+++ b/cal/trans.py
@@ -23,6 +23,11 @@ class Trans:
             "en":"argon",
             "mol_weigth":"39.948"
         },
+        "H2":{
+            "de":"Wasserstoff",
+            "en":"hydrogen",
+            "mol_weigth":"2.016"
+        },        
         "Kr":{
             "de":"Krypton",
             "en":"krypton",