diff --git a/include/open_atmos/mechanism_configuration/validation.hpp b/include/open_atmos/mechanism_configuration/validation.hpp
index ff4224f..6f5de43 100644
--- a/include/open_atmos/mechanism_configuration/validation.hpp
+++ b/include/open_atmos/mechanism_configuration/validation.hpp
@@ -86,7 +86,7 @@ namespace open_atmos
     struct Arrhenius
     {
       const std::vector<std::string> required_keys{ keys.products, keys.reactants, keys.type, keys.gas_phase };
-      const std::vector<std::string> optional_keys{ keys.A, keys.B, keys.C, keys.D, keys.E, keys.name };
+      const std::vector<std::string> optional_keys{ keys.A, keys.B, keys.C, keys.D, keys.E, keys.Ea, keys.name };
     } arrhenius;
 
     struct Mechanism
diff --git a/src/parser.cpp b/src/parser.cpp
index 440830f..6bc9552 100644
--- a/src/parser.cpp
+++ b/src/parser.cpp
@@ -317,7 +317,8 @@ namespace open_atmos
         for (const auto& product : object[validation::keys.products])
         {
           auto product_parse = ParseReactionComponent(product);
-          if (product_parse.first != ConfigParseStatus::Success) {
+          status = product_parse.first;
+          if (status != ConfigParseStatus::Success) {
             break;
           }
           products.push_back(product_parse.second);
@@ -327,7 +328,8 @@ namespace open_atmos
         for (const auto& reactant : object[validation::keys.reactants])
         {
           auto reactant_parse = ParseReactionComponent(reactant);
-          if (reactant_parse.first != ConfigParseStatus::Success) {
+          status = reactant_parse.first;
+          if (status != ConfigParseStatus::Success) {
             break;
           }
           reactants.push_back(reactant_parse.second);
@@ -386,7 +388,7 @@ namespace open_atmos
           requested_species.push_back(spec.species_name);
         }
 
-        if (RequiresUnknownSpecies(requested_species, existing_species)) {
+        if (status == ConfigParseStatus::Success && RequiresUnknownSpecies(requested_species, existing_species)) {
           status = ConfigParseStatus::ReactionRequiresUnknownSpecies;
         }
 
diff --git a/test/integration/test_json_parser.cpp b/test/integration/test_json_parser.cpp
index 1a73d81..c49b2de 100644
--- a/test/integration/test_json_parser.cpp
+++ b/test/integration/test_json_parser.cpp
@@ -12,4 +12,11 @@ TEST(JsonParser, ParsesFullConfiguration)
   EXPECT_EQ(mechanism.name, "Full Configuration");
   EXPECT_EQ(mechanism.species.size(), 10);
   EXPECT_EQ(mechanism.reactions.arrhenius.size(), 1);
+}
+
+TEST(JsonParser, ParserReportsBadFiles)
+{
+  JsonParser parser;
+  auto [status, mechanism] = parser.Parse(std::string("examples/_missing_configuration.json"));
+  EXPECT_EQ(status, ConfigParseStatus::InvalidFilePath);
 }
\ No newline at end of file
diff --git a/test/unit/test_parse_arrhenius.cpp b/test/unit/test_parse_arrhenius.cpp
index ebe5a52..e26fba1 100644
--- a/test/unit/test_parse_arrhenius.cpp
+++ b/test/unit/test_parse_arrhenius.cpp
@@ -68,4 +68,18 @@ TEST(JsonParser, ArrheniusDetectsUnknownSpecies)
   JsonParser parser;
   auto [status, mechanism] = parser.Parse(std::string("unit_configs/reactions/arrhenius/unknown_species.json"));
   EXPECT_EQ(status, ConfigParseStatus::ReactionRequiresUnknownSpecies);
+}
+
+TEST(JsonParser, ArrheniusDetectsMutuallyExclusiveOptions)
+{
+  JsonParser parser;
+  auto [status, mechanism] = parser.Parse(std::string("unit_configs/reactions/arrhenius/mutually_exclusive.json"));
+  EXPECT_EQ(status, ConfigParseStatus::MutuallyExclusiveOption);
+}
+
+TEST(JsonParser, ArrheniusDetectsBadReactionComponent)
+{
+  JsonParser parser;
+  auto [status, mechanism] = parser.Parse(std::string("unit_configs/reactions/arrhenius/bad_reaction_component.json"));
+  EXPECT_EQ(status, ConfigParseStatus::RequiredKeyNotFound);
 }
\ No newline at end of file
diff --git a/test/unit/unit_configs/reactions/arrhenius/bad_reaction_component.json b/test/unit/unit_configs/reactions/arrhenius/bad_reaction_component.json
new file mode 100644
index 0000000..859209d
--- /dev/null
+++ b/test/unit/unit_configs/reactions/arrhenius/bad_reaction_component.json
@@ -0,0 +1,37 @@
+{
+  "version": "1.0.0",
+  "name": "Mutually Exclusive",
+  "species": [
+    {
+      "name": "A"
+    },
+    {
+      "name": "B"
+    }
+  ],
+  "phases": [
+    {
+      "name": "gas",
+      "species": [
+        "A",
+        "B"
+      ]
+    }
+  ],
+  "reactions": [
+    {
+      "type": "ARRHENIUS",
+      "gas phase": "gas",
+      "reactants": [
+        {
+          "Species name": "A"
+        }
+      ],
+      "products": [
+        {
+          "species name": "B"
+        }
+      ]
+    }
+  ]
+}
\ No newline at end of file
diff --git a/test/unit/unit_configs/reactions/arrhenius/mutually_exclusive.json b/test/unit/unit_configs/reactions/arrhenius/mutually_exclusive.json
new file mode 100644
index 0000000..61db970
--- /dev/null
+++ b/test/unit/unit_configs/reactions/arrhenius/mutually_exclusive.json
@@ -0,0 +1,39 @@
+{
+  "version": "1.0.0",
+  "name": "Mutually Exclusive",
+  "species": [
+    {
+      "name": "A"
+    },
+    {
+      "name": "B"
+    }
+  ],
+  "phases": [
+    {
+      "name": "gas",
+      "species": [
+        "A",
+        "B"
+      ]
+    }
+  ],
+  "reactions": [
+    {
+      "type": "ARRHENIUS",
+      "gas phase": "gas",
+      "reactants": [
+        {
+          "species name": "A"
+        }
+      ],
+      "products": [
+        {
+          "species name": "B"
+        }
+      ],
+      "C": 10,
+      "Ea": 0.5
+    }
+  ]
+}
\ No newline at end of file