diff --git a/borman-exercise-3-11.ipynb b/borman-exercise-3-11.ipynb
index ed75998..f81fb2b 100644
--- a/borman-exercise-3-11.ipynb
+++ b/borman-exercise-3-11.ipynb
@@ -215,7 +215,29 @@
     }
    ],
    "source": [
-    "print (mix.species_moles / mix.species_moles.sum())"
+    "Xi = mix.species_moles / mix.species_moles.sum()\n",
+    "print (Xi)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "H2\t0.2658277399325119\n",
+      "CO\t0.5991610732658453\n",
+      "H2O\t0.06750559340082132\n",
+      "C(gr)\t0.06750559340082132\n"
+     ]
+    }
+   ],
+   "source": [
+    "for tup in zip(mix.species_names, Xi):\n",
+    "    print (\"{}\\t{}\".format(*tup))"
    ]
   }
  ],