# Mechanical Energy of Amonia Molecule

In summary, the ammonia molecule has a tetrahedral structure with three hydrogen atoms forming a triangle in the xy-plane and a nitrogen atom at the apex. The potential energy of the nitrogen atom is shown in a graph with a Z-axis perpendicular to the H3 triangle. At room temperature, the nitrogen atom has a mechanical energy of .4*10^-20J and moves periodically in a potential well, unable to go beyond the blue line. If the energy is 2*10^-20J, the nitrogen atom can cross the plane of the three hydrogen atoms during its motion.
Mechanical Energy of Amonia Molecule [SOLVED]

## Homework Statement

The ammonia molecule has the tetrahedral structure shown in the figure (Intro 1 figure) . The three hydrogen atoms form a triangle in the xy-plane at z = 0. The nitrogen atom is the apex of the pyramid. The figure (Intro 2 figure) shows the potential energy of the nitrogen atom along a Z-axis that is perpendicular to the H3 triangle.

A.)At room temperature, the nitrogen atom has .4*10^-20J of mechanical energy. Describe the position and motion of the nitrogen atom.

B.)The nitrogen atom can gain energy if the molecule absorbs energy from a light wave. Describe the motion of the nitrogen atom if its energy is 2*10^-20J.

## Homework Equations

Figure 1:
http://img694.imageshack.us/img694/6085/10p60a.jpg
Figure 2:
http://img294.imageshack.us/img294/5705/10p60b.jpg

## The Attempt at a Solution

Absolutely no idea! >.<

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The nitrogen atom is confined in the potential well shown in the figure. Draw a horizontal line at hight of the total energy: this line represents the motion of the atom inside the potential well. It can not go over the blue line, but moves periodically between the borders of the well. At the position z where the horizontal line crosses the blue line, the atom has no KE. At other positions, its KE is the difference of the total energy and the potential energy.

In the first case, the atom moves either in the left or in the right well, as it s energy is lower than the barrier of about 1.2 x10-20 J. If the energy is 2x10-20 J the N atom crosses the plane of the three hydrogen atoms during its motion.

ehild

Thanks, I think I understand the problem now!

## 1. What is mechanical energy of an ammonia molecule?

Mechanical energy of an ammonia molecule is the sum of its kinetic energy (energy of motion) and potential energy (energy due to its position or arrangement of atoms).

## 2. How is mechanical energy related to the movement of an ammonia molecule?

The kinetic energy of an ammonia molecule is directly related to its movement, as it is determined by its mass and velocity. The potential energy, on the other hand, is related to the bonding and arrangement of atoms within the molecule.

## 3. Can mechanical energy be converted into other forms of energy in an ammonia molecule?

Yes, mechanical energy can be converted into other forms of energy in an ammonia molecule. For example, when an ammonia molecule undergoes a chemical reaction, the potential energy stored in its bonds can be released as heat or light energy.

## 4. How does temperature affect the mechanical energy of an ammonia molecule?

Temperature is directly related to the kinetic energy of an ammonia molecule. As the temperature increases, the molecules will have a higher velocity and therefore a higher kinetic energy. However, the potential energy of the molecule will remain the same.

## 5. Is mechanical energy a constant value in an ammonia molecule?

No, mechanical energy is not a constant value in an ammonia molecule. It can change depending on the molecule's movement, interactions with other molecules, and any chemical reactions it undergoes.

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