SNC 1P Mr. M. Couturier

Electrical Charge Recall from the chemistry unit that when electrons are exchanged, ions are created. When the number of protons in an atom does not equal the number of electrons, we say that we have an electrical or electric charge. This will be the basis of electricity (note the root of the word in relation to electron).

Electrical Charge

When the imbalance of electrical charge is such that there are more protons than electrons, then we say that the object is positively charged. NOTE: Electricity is the exchange of electrons only. Protons are never exchanged in electricity.

Electrical Charge

We therefore say that when there are more electrons than protons, we have a negatively charged object. Naturally, an object where the electrons equal the protons, is a neutral object.

Electrical Charge Nature is always seeking balance. It will want to neutralize objects (recall ionic bonds which are electrically attractive but neutral when combined). When objects rub against each other or collide, they exchange electrons in the direction of objects which desire their electrons against those that have trouble retaining their electrons.

Electrical Charge Objects that have like charges repel each other. Objects that have opposite charges attract each other. This implies that an electric force will either push apart two objects (repulsive force) or pull them together (attractive force).

Electrical Charge Na and Cl form a very strong bond because when the Na's electron is given to Cl, Na becomes positively charged while Cl becomes negatively charged. They then are electrically attracted to each by an electric force of attraction.

Electrical Charge Charging objects by friction requires that you understand the electrostatic series. See table.

Electrical Charge

Referring to your table, if human hair and a rubber balloon are rubbed against each other, where do the electrons go?

Electrical Charge Since the rubber balloon has a stronger desire for the electrons, the electrons will travel from the human hair to the rubber balloon. Both objects are now charged! The human hair has an electrical imbalance such that there are more protons than electrons; hence the human hair is positively charged.

Electrical Charge Meanwhile, since the electrons from the human hair have moved to the rubber balloon, it is now negatively charged as it has more electrons than protons.

Electrical Charge