{"id":3439,"date":"2024-05-17T17:38:48","date_gmt":"2024-05-17T17:38:48","guid":{"rendered":"https:\/\/www.aceorganicchem.com\/blog\/?p=3439"},"modified":"2024-05-17T17:38:50","modified_gmt":"2024-05-17T17:38:50","slug":"molecular-geometry-of-no2-with-video-and-free-study-guide","status":"publish","type":"post","link":"https:\/\/www.aceorganicchem.com\/blog\/molecular-geometry-of-no2-with-video-and-free-study-guide\/","title":{"rendered":"Molecular Geometry of NO2- [with video and free study guide]"},"content":{"rendered":"\n

What is the molecular geometry of NO2<\/sub>–<\/sup>?<\/strong><\/h1>\n\n\n\n

The molecular shape of NO2<\/sub>–<\/sup> is bent, or AX2<\/sub>E using Valence Shell Electron Pair Repulsion (VSEPR) theory. Hence, the molecular geometry of NO2<\/sub>–<\/sup> only has 134 degree bond angles in the molecule. NO2<\/sub>–<\/sup> looks like this:<\/p>\n\n\n\n

\"molecular<\/a><\/figure>\n\n\n\n

How do you find the molecular geometry of NO2<\/sub>–<\/sup><\/strong>? <\/strong><\/h2>\n\n\n\n

There is an easy three-step process for determining the geometry of molecules with one central atom.<\/p>\n\n\n\n

Step 1<\/strong>: Determine the Lewis structure of the molecule.<\/em>
For NO2<\/sub>–<\/sup>, it is as shown below: For a full-explanation of how to figure out the Lewis structure, please go to Lewis Structure of NO2<\/sub>–<\/sup>.<\/p>\n\n\n\n

\"Lewis<\/figure>\n\n\n\n

Step 2<\/strong>: Apply the VSEPR notation to the molecule.<\/em>
Apply VSEPR notation, A X E
A=Number of central atoms
X=Number of surrounding atoms
E= Number of lone pairs on central atom
For this one, we can see that it has one central atom, two surrounding atoms, and one lone pair of electrons around the central atom, making it AX2<\/sub>E. For the purposes of VSEPR, we are determining the geometry of the nitrogen atom, so we ignore the negative charge on the oxygen.<\/p>\n\n\n\n

Step 3<\/strong>: Use the VSEPR table to determine the geometry of NO2<\/sub>–<\/sup>.<\/em><\/p>\n\n\n\n

\"VSEPR<\/a><\/figure>\n\n\n\n

As you can see from the chart, AX2<\/sub>E molecule <\/strong>is bent. <\/strong><\/h2>\n\n\n\n

Bond angles help show molecular geometry of <\/strong>NO2<\/sub>–<\/sup><\/h3>\n\n\n\n

There is only one bond angle in this molecule. It is the O-N-O bond angle, which is 132 degrees. Even though one is a double bond and the other is a single bond, they are actually the same because of resonance, a process where the single and double bond are changing places so rapidly that they act like it is 1.5 bonds between the O and N. <\/p>\n\n\n\n

\"NO2-<\/a><\/figure>\n\n\n\n
\"NO2-<\/figure>\n\n\n\n

Also, it is important to remember that there is a negative charge on the oxygen that has only one bond, giving the overall molecule a negative charge. <\/p>\n\n\n\n

\"molecular<\/figure>\n\n\n\n

More about VSEPR and the molecular geometry of NO2<\/sub>–<\/sup>:<\/strong><\/h3>\n\n\n\n

Let’s not forget, the whole purpose of VSEPR is to minimize interactions between the substituents (atoms and lone pairs) of a molecule. We also know that electrons repel each other. Hence, simple molecules (like the ones we are looking) at will tend to place substituent atoms as far from each other as possible. We know this because of the bond angles associated with each of the four types of shapes.<\/p>\n\n\n\n

\"VSEPR<\/a><\/figure>\n\n\n\n

Here is one way to remember this chart: Think about each lone pair as just replacing an atom. In the chart above we have tried to show how this works by just blurring out an atom for a lone pair. <\/p>\n\n\n\n

For the 3 and 4 substituent molecules (AX3<\/sub> group and AX4 <\/sub>group, respectively) it is easy to do this because each one of the substituent atoms is the same. So for AX2<\/sub>E, it is simple to see that we get trigonal pyramidal as the answer because we can replace any of the atoms with a lone pair because they are all geometrically equivalent. Same for AX3<\/sub>E because all of the atoms are geometrically equivalent. <\/p>\n\n\n\n

It get a little trickier when we get to the 5 and 6 substituent molecules (AX5<\/sub> group and AX6 <\/sub>group, respectively). Here, there is a geometric difference between the atoms on the axis (called axial substituents) and the ones around the middle, called the equatorial substituents. Thus, we can’t just substitute a lone pair for any old atom. So…..what we need to remember is that for the AX5<\/sub> group, you need to replace equatorial atoms with lone pairs AND for the AX6<\/sub> group, you need to replace the atoms on the axis with lone pairs, as we have shown above. <\/p>\n\n\n\n

Some video to make it a little simpler:<\/strong><\/h3>\n\n\n\n
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