Periodic Table Layout then monoatomic ion formation.

Periodic Table Layout thenmonoatomic ion formation. OBJECTIVE... What is the general layout of the periodic table?,and then,why and how do ions form from atoms?Welcome to chapter 6 in the textbook, which you should always read.

The periodic table, in all its glory. Chemistry is so cool.

Up and Down columns on the table are called GROUPS Groups share chemical properties. LEFT to RIGHT rows on the table are called PERIODS. Periodic table periods have the same number of electron orbitals. DO NOT MIX THAT UP. Gilbert needs goggles!

Make sure you see which are metals, which are NON-metals

LOOK AT YOUR REFERENCE TABLE NOW. FIND THE DARK BLACK “staircase” LINE on the right side. On the left are metals, on the right are the non-metals. THERE ARE 7 METALLOIDS, write them onto your periodic table.

All elements that are metals have some similar properties • They conduct electricity • They are malleable • They are ductile • They conduct heat • They have relatively high melting points • They are lustrous • They have relatively high densities • They also share many chemical properties making steel

Metal Groupings for you • GROUP 1, the alkali metals • GROUP 2, the alkaline earth metals • GROUPS 3 to 12 (plus), the transitional metals • the 7 METALLOIDS are not a punk rock band, they are metals with some “cross-over” non-metallic properties. They are STILL metals, but because of their unusual extra properties, they are also known as the 7 Metalloids.

GET THE PICTURE?

If it ain’t a metal, then it’s a non-metal... • Working back from the right side of the table • GROUP 18 are the NOBLE GASES • GROUP 17 are the HALOGENS (except for At)(the picture is a bit wrong but it’s nice)

At room temperature and normal air pressure All the metals are solids (except for mercury!) All the non-metals are solids or gases (except bromine is a liquid) Bromine as a liquid at the bottom, and as a gas at the top of the bottle. solid gold bars

SIMILARITIES of the GROUPS atoms are arranged in the Periodic Table by GROUP. The groups share many chemical properties. Look at group on and notice the electron configurations. What is the same about each one? Li 2-1 Na 2-8-1 K 2-8-8-1 Rb 2-8-18-8-1 Cs 2-8-18-18-8-1 Fr 2-8-18-32-18-1 Cs + H2O BOOM

Now check out GROUP 2 look at their electron configurations Be 2-2 Mg 2-8-2 Ca 2-8-8-2 Sr 2-8-18-8-2 Ba 2-8-18-28-8-2 Ra 2-8-18-32-18-8-2 A salt, strontium sulfate, has a characteristic color flame, as the electrons return to the ground state, they emit a unique energy mixture.

All groups of atoms have the same number of electrons in the outermost orbital. Those are called VALENCE ELECTRONS. How many electrons in the valence orbital for these groups? Group 3 Group 18 Group 17 Group 16 Group 15

This Is Crazy. Are you ready??? Atoms are neutral and they like that. Given a choice though, they’d much rather have a complete outer orbital and give up neutrality. That means that some atoms will tend to lose some electrons, others would gain some electrons. They turn into. IONS How cool is that?

Example one... Lithium has an electron configuration of 2-1 It’s neutral since it has 3 protons and 3 electrons. NORMAL. It would be happier to have a complete outer orbital, and since losing one electron is simpler than gaining seven (eight electrons fit in the second orbital), that is what it does. SO... Li 2-1 becomesLi 2(minus that electron in the second orbital)with one less electron. The loss of a negative charge makes the resulting ion have a +1 charge, written as Li+1

Draw this chart into your notes. Fill in the blanks too.

Fill in as you go... Positive Ions are called CATIONS

If you have a cat, you know that a cat is a POSITIVE addition to your home. If you don’t have a cat, or don’t like cats, just try to imagine how POSITIVE a cat could be if you just gave it a try. POSITIVE IONS, atoms that LOSE electrons, become CATIONS

The Opposite of Cations Some atoms will not lose electrons, since getting a full outer orbital (the valence orbital) is what they want. They find gaining a few electrons is easier than losing a bunch, so that’s what they do. Atoms that gain electrons become more negative. These negatively charged ions are called ANIONS

Let’s look at some non-metals now, which will have an easier time gaining electrons to secure a complete outer orbital. Draw this chart into your notes. Fill in the blanks too

Review so far... Atoms are neutral because the + protons = in number to the - electrons. Atoms like to be neutral Most atoms, given opportunity, would prefer to have complete outer orbitals rather than be neutral. Atoms that lose electrons to get that complete outer orbital are losing negative charge, so they become positively charged cations. Atoms that gain electrons to get that completer outer orbital are gaining negative charge, so they become negatively charged anions. Gaining or losing electrons is all based upon the electron configurations. All atoms in a group (up and down) have the same number of electrons in their outer orbitals. All atoms in a group make the same kind of cation, or same kind of anion. Metals always make cations, they lose electrons. Non-metals always make anions, they gain electrons. Metals can’t give away electrons to the universe in general, they have to find willing non-metals to accept them (or they are stuck neutral). You truly have to grasp each point of this slide to make any more progress.

Sodium chloride is table salt, it is an ionic compound, formed by sodium cations combining to chlorine anions. Way cool. When cations get near anions, they are attracted to each other, opposite charges attract. They form IONIC COMPOUNDS, compounds that are made from ions. All ionic compounds are net neutral, so the number of positive charges from the cations must equal the negative charges of the anions. There are never left over electrons, or electron IOU’s.

Periodic Table Layout then monoatomic ion formation.