sci 5.2
1) Contrast sodium and chloride ions, including how they form. Write the symbol for each ion.
1.A) Sodium (Na) forms a +1 ion à Na+1 because it has one valence electron so it easier to take away that one electron making it a positive charge than to add 7 electrons.
1) Contrast sodium and chloride ions, including how they form. Write the symbol for each ion.
1.B) Chlorine (Cl) forms a -1 ion à Cl-1 because it has 7 valence electrons so adding one electron gives it 8 making it happy and -1 charge
5) Relate each property that you listed to the characteristics of ionic bonds.
5.A) Crystal structure- because of the strength of the ionic bonds and because the ions are attracted to all the oppositely charged ions around them in a regular pattern that forms a crystal.
5) Relate each property that you listed to the characteristics of ionic bonds.
5.B) High melting point- p. 162 Ionic compounds have a high melting point because it takes a lot of energy to make them separate. That's when the crystal melts to a liquid. They are strong and a lot of energy (heat) is needed to break them so they have high melting points.
5) Relate each property that you listed to the characteristics of ionic bonds.
5.C) Conduct electricity when melted or dissolved- p. 163 Ionic compounds are good conductors of electrical current when they dissolve in water because the ions are free and loose and the current can get through. But ions in a solid crystal are tightly bound and so not good conductors of electricity.
4) List three properties of ionic compounds.
A) Are hard brittle crystals B) If they are melted or dissolved in water they conduct electricity C) They have high melting points
3) Write the formula for calcium chloride. Explain how you determined this formula.
CaCl2. This is the formula because Calcium has a charge of +2 and Chloride ion has a charge of -1 so when they combine to be neutral you need two chloride ions to even out the +2 charge of the Calcium. So you bring down the 2 as a subscript for the ratio of 1 Calcium for every 2 Chlorides.
2) What information is given by the formula of an ionic compound?
The formula of an ionic compound tells you ratio of the ions of each element (how many of each are needed when they combine). It also tells you which ion is the positive one since that is the one named first.
