Examples of Gravitational Potential Energy

Energy and State of Matter Particles has the highest kinetic energy when they are in the gaseous state. Kinetic energy is related to heat (also called thermal energy). Raising the temperature results in an increase of its kinetic energy.

Glucose

• A raised weight.
• Water that is behind a dam.
• A car that is parked at the top of a hill.
• A yoyo before it is released.
• River water at the top of a waterfall.
• A book on a table before it falls.
• A child at the top of a slide.
• Ripe fruit before it falls.

Potential energy is energy that is stored in an object or substance. Gravitational potential energy is energy in an object that is held in a vertical position. Elastic potential energy is energy stored in objects that can be stretched or compressed.

A potential energy diagram shows the change in potential energy of a system as reactants are converted into products. The activation energy for a reaction is illustrated in the potential energy diagram by the height of the hill between the reactants and the products.

The potential energy measures the energy stored within the bonds and phases of the reactants and products. This potential energy is a part of the internal energy. In chemical reactions, the internal energy represents the total energy of the system and is often called enthalpy.

U.

The following steps detail how to draw an Aufbau diagram:

1. Determine the number of electrons that the atom has.
2. Fill the s orbital in the first energy level (the 1s orbital) with the first two electrons.
3. Fill the s orbital in the second energy level (the 2s orbital) with the second two electrons.

The energy levels are built up from the level closest to the nucleus outward. This process of filling in the electrons from the first, lowest energy level to the second, slightly higher energy level to the third, even higher energy level is called filling the electrons in by the Aufbau Principle.

O2 has two unpaired electrons in its π* orbitals, and a bond order of 2. The simple Lewis structure has all electrons paired, which does not match the paramagnetism observed experimentally.

In writing the electron configuration for oxygen the first two electrons will go in the 1s orbital. Since 1s can only hold two electrons the next 2 electrons for O go in the 2s orbital. The remaining four electrons will go in the 2p orbital. Therefore the O electron configuration will be 1s22s22p4.

Suppose you want to draw the energy level diagram of oxygen. You look on the periodic table and find that oxygen is atomic number 8. This number means that oxygen has 8 protons in its nucleus and 8 electrons. So you put 8 electrons into your energy level diagram.

8

The electrons surrounding an atom are located in regions around the nucleus called “energy levels”. An energy level represents the 3-dimensional space surrounding the nucleus where electrons are most likely to be. When the third energy level has 8 electrons, the next 2 electrons go into the fourth energy level.

valence electrons

There are four types of orbitals that you should be familiar with s, p, d and f (sharp, principle, diffuse and fundamental). Within each shell of an atom there are some combinations of orbitals.