Its a 50% chance that approx 1/2 of the pennies will land on tails. The next toss will result the same. and so on and so on. showing how a reaction would slowly eliminate 1/2 of the remaining lives per reaction, until nothing is left. I think it is a good stimulation.
EASY AS PIE AND I LIKE PIE
Calcium iodide (CaI2) is an ionic bond, which means that electrons are transferred. In order for Ca to become the ion Ca2+, the calcium atom must lose 2 electrons. (Electrons have a negative charge, so when an atom loses 2 electrons, its ion becomes more positive.) In order for I to become the ion I1−, the iodine atom must gain 1 electron. (When an atom gains an electron, its ion will be more negative.) However, the formula for calcium iodide is CaI2 - there are 2 iodine ions present. This makes sense because the iodine ion has a charge of -1, so two iodine ions have to be present to cancel out the +2 charge of the calcium ion. Therefore, the calcium atom transfers 2 valence electrons, one to each iodine atom, to form the ionic bond.
IF WRONG, SORRY
Explanation:
Percentage composition = 2/18 = 11.11%.