The Happy Atom Story

Calcium’s Electrons Become Guy’s Teachers
Calcium continued, “Professor Terry, you're message told me that Guy needed to learn about electrons today.” He then added, “I’ll take good care of Guy and make sure he learns everything he needs to know about electrons. You can expect us to be finished about three o’clock.”
“Wonderful!” said Professor Terry, and with a friendly wave she left.
Calcium moved closer to Guy and whispered, “My electrons have not been behaving this morning. Wait here while I get them squared away before you come in.”
Calcium went inside, and Guy heard him scolding the electrons, “You naughty little electrons stop playing and get back in your proper energy levels. We have company. Guy is here. Act like you know that Guy has come specifically to see you.”
The electrons got back in their energy levels where they belonged. Then Guy entered Calcium’s house and in chorus, the electrons sang his welcome. “Hi Guy, what would you like to know about us?”
Guy was delighted to hear the little electrons’ singing voices. It was a pleasant welcome he did not expect. Then Guy responded, “I want to know everything about you! But before we get started, I do have one question that has been troubling me since I read about electrons in my book. The book said that the electrons were located in an ‘electron cloud’ around the nucleus. The atomic models I’ve seen had electrons in special places around the nucleus called energy levels. Which is it?”
The electrons giggled and called out together, “We’re in both! We are each in our assigned energy level at special distances from the nucleus. The models you saw were just still pictures of our energy levels. In real life, we are in these specific areas, but we are moving at such high speeds around the nucleus that we look like a cloud. As we move, we remain in areas at our special distances from the nucleus called energy levels. We’re kind of like the blades of a fan when they’re moving at high speed. The blades look like just one big blur. Our motion creates the look of a cloud which some people call ‘the electron cloud’ because we are in there.”
“Well now, that makes a lot of sense,” said Guy. “Thank you, my little electron friends.”
Calcium walked closer to talk to Guy and said, “Electrons are very small, but there are quite a number of things you need to learn about them. My little electrons are excited to be your teachers today.”

Electrons Like to Travel in Pairs
One little electron piped up, “Did you know we like to travel in pairs? We stay close to our partner as we whirl around the nucleus in our assigned energy level. We like being close to each other. Our negative charges make this difficult, but we have learned spinning in opposite directions overcomes our negative repelling forces. We electrons are clever.”
The outside electron objected. “Well not always! If you are in the Outside Energy Level, you might not have a partner. This is true for elements whose Atomic Numbers are not even numbers. If the Atomic Number is an odd number, then one electron has to travel alone. I’m lucky. Calcium’s Atomic Number is 20, an even number. There are two of us in the outside energy level. We don’t have to travel alone. It’s so good to have a partner. Look back at the model of our Calcium atom (Diagram A) and see all the electrons traveling in pairs. We look like e-e- in the energy levels just like we told you.”
Calcium whispered to Guy, “These little electrons are amazing.”

Electrons Tell Guy About Their Negative Charge
The second electron interrupted, “I’ve got to tell you something exciting about us. Some people are boring, but never accuse electrons of being boring. We are charged! As a matter of fact, we have a negative charge. That’s what that little minus sign after the electron (e-) means. Have you ever walked across a rug, touched a doorknob, and suddenly felt a shock? Well, as you walk across a rug, your shoes pick up electrons from the rug and fill your body with extra electrons. What you feel when you touch the door knob is the charge of electrons leaving your body. We electrons are so charged! We’re rather fun to be around.”
Guy reflected, “So that’s why I got such a shock when my cousin shuffled across the rug and touched my nose!” The electrons nodded, and sang, “Kids! Kids! Have so much fun. We electrons give them so much fun!”

Guy Learns About the Protons’Positive Charges
“I hope you tell Guy that we are not the only ones with a charge,” said a serious little electron wanting to keep the facts straight. “Protons have charges, too. That’s what the plus sign (+) means when we write protons as p+ in the nucleus of the atom. Their charge is a positive charge, but it is all locked up in the nucleus. You don’t feel the charge of the proton the way you feel our charge.”
“That’s exactly my point,” the second little electron said, “We electrons just have more fun with our charges.”
The little electron continued, “The protons' positive charges are doing something absolutely necessary. I’m sure you know that opposite charges attract each other. It’s like the opposite ends of magnets that attract each other. You probably have played with magnets and experienced the way the magnets pull each other together. We electrons have negative charges. So the protons' positive charges are attracting our negative charge holding all our electrons in place around the nucleus. For this we should be thankful. It’s the positive charges on the protons that keep the electrons with their negative charges from flying off.”