Lab 3.1: Properties of Ionic and Covalent Compounds

1. Ionic compounds generally have a high melting point, dissolve in water, and conduct electricity.
2. Covalent substances generally have a low melting point, don't dissolve in water, and don't conduct electricity.
3. Ionic bonds form from a metal and a non metal. The electrons are transferred.
4. Covalent bonds form from two non metals. The electrons are shared.
5. Covalent bonds don't conduct electricity because the electrons are fixed in one place and can't move freely.
6. When in solid form, ionic substances electrons can't move freely. Dissolving them separates the ions and allows them to move around.
Enrichment: When athletes sweat, they lose electrolytes. These electrolytes are needed to perform muscle function. The most commonly used electrolytes are dissolved metal salts. Some electrolytes used are Potassium, sodium, and chloride.

Lab 3.1: Modeling Molecules

1. I think the bond between ions is stronger than the bond between molecules because most ionic bonds have a higher melting point. Ionic bonds are also electrically attracted to each other, while molecules are not.

2.When you melt something, it's a physical change. Physical changes don't rearrange the atoms, chemical changes do. Therefore if you melted HCl molecules, they would not seperate.


3. When ionic substances are melted, the molecules are free to move around and create a charge.

4. Molecular substances do not create a charge because molecules have a neutral charge.

 Enrichment:
                    A polar molecule is a molecule with a bond from having two atoms with opposite charges. Water is a polar molecule.

Blog 2.2 Bag of Ions and Periodic Table

             The periodic table is arranged by groups and periods. The groups are vertical columns that go by number of valence electrons. The periods are horizontal rows that increase going down in number of electron shells. The noble gasses are all on the right side, and they have full valence electron shells.

   Ions of the same element have the same number of protons and mass, but they have a different number of electrons, valence electrons, and neutrons. An ion is formed when an element gains or loses electrons. If it loses electrons, it becomes more positively charged, as electrons have a negative charge. If it gains electrons, it has more of a negative charge. If you look on the periodic table, you will see the elements electron configuration. This also shows how many valence electrons an element has. You can see the charge in the top right corner.

Lab 2.1 Grouping of Elements

1. The groupings of elements we made were:
Aluminum and lead
Carbon, Silicon, and Tin
Sulfur and phosphorous.

2.Appearance- Physical. It doesn't have to do with anything chemically, it's just how it looks.
   Electrical conductivity- Chemical. Depending on what kind of atoms make up the element decides if it will hold an electric current.
   Crush Test- Chemical. It depends on how tightly the atoms are packed together.
   Reactivity With Acid- Chemical. An element reacting with something is a chemical property because it depends on how the atoms are formed.

3. A. What is unique about metalloids is that they can have properties of both metals and non metals, depending on the conditions.
   B. Silicon. It is shiny, has some electrical conductivity, is brittle and does not react with acid.
   C. Boron- B, Silicon- Si, Germanium- Ge, Arsenic- As, Antimony- Sb, Tellurium- Te, and Polonium- Po.
 
4.From top to bottom, the elements go from shiny to dull.
   From right to left, the elements go from dull to shiny.

Enrichment:
           Silver-Ag comes from the latin word argentum, which means 'white metal' in English.