0.6394139898665671 that’s how many moles are in 25g of potassium !
In the average classroom. You have AC and DC energy that flows through the wires and powers your computers, phones, projector (if you have one), the light-bulbs in the ceiling or around the room. Their is potential energy when an object is at rest for example your pencil or desk, There is Kinetic energy when objects are moving for example if you walk around or something is rolling around. You yourself is an example of energy.<span />
Use your senses, so sound, smell( pls waft), change in color or tempurature, bubbles, or light
