Presentation on theme: "Ions and Isotopes Objective Students will be able to:"— Presentation transcript:
1 Ions and Isotopes Objective Students will be able to: use atomic symbols to represent different atoms and their isotopes.Identify and define ions of different elements
2 How does something have a positive or negative charge? Some definitionsIon - an atom that has a positive or negative chargeHow does something have a positive or negative charge?Number of protons and electrons has to be different!
3 How can an atom become an ion? By gaining or losing electronsLosing Electrons= CATIONGaining Electrons= ANION
4 Cation Positive charge Formed by the atom losing electrons A neutral atom of sodium loses an electron and becomes Na+1How many electrons does Li+1 have? Mg+2?
5 Anion Negative charge Formed by the atom gaining electrons Chlorine gains one electron and becomes Cl-1How many electrons does Br-2 have? F-1??
6 Why do atoms become ions? Atoms want to have a full outer shell (orbital)one electron in outer shell will lose the electron.all but one electron will gain one.Which is likely to become a cation?Which is likely to become an anion?
7 Summary of Ions Lose electrons- become positive, which is a cation Gain electrons- become negative, which is an anionElectrons are gained or lost in the outermost shellThese are called valence electrons
8 Atomic Notation Mass number= protons + neutron Element Symbol Atomic number= ProtonsP=N=E=20P=N=E=7
10 IsotopesIsotopes are atoms of the same element that have different numbers of neutrons.The mass number of an isotope tells you the number of protons plus the number of neutrons.Difference?Similarities?H H-2 H-3
11 Learning CheckNaturally occurring carbon consists of three isotopes, 12C, 13C, and 14C. State the number of protons, neutrons, and electrons in each of these carbon atoms.12C C C#p _______ _______ _______#n _______ _______ _______#e _______ _______ _______
13 Heavy Water Application of isotope Duterium- 21H can bind with oxygenOnly occurs 1 in every 3200 moleculesConcentrated heavy water is used for development of nuclear weaponsCan be poisonous to plants and animals.
14 Cobalt-60 Application of isotope Has one extra neutron in the nucleusRadioactive and emits gamma radiation, which can pass through materials easilySterilizes medical equipment and kills harmful bacteria