An atom is made up of protons, neutrons, and electrons. The protons carry a positive charge and make up the nucleus of an atom with the neutrons. Neutrons do not carry a charge. The electrons carry a negative charge and circle the nucleus. Atoms have no positive or negative charge. This means that they must have the same number of protons and electrons. A partial model of a nitrogen atom is shown. How many electrons should be drawn on the model of a nitrogen atom so that it has the same number of protons and electrons? How did you know? Complete the model of the nitrogen atom by drawing in the electrons. Write a number sentence to represent the sum of the number of protons and electrons in a nitrogen atom. Use a number line to show the sum of the number of protons and electrons in the nitrogen atom.