Lessons 6-10

In class on Friday we learned that matter cannot be created or destroyed. The next main point was the periodic table. We learned how it was organized, such as elements in each column (Period) have similiar properties and what the writing in each idividual box meant. Atomic number, atomic mass, so on and so forth. There is a picture that represents this below. To help understand these similarities we did an activity where we organized the periodic table using cards which listed each element's atomic mass and number, reactivity and phase at room temperature. This helped to understand the placement of each element.




Chapter 6 Practice Problems
1. Describe the difference between an element and a compound.
An element is a building block of matter that can not be brokendown any farther by chemical means. A compound is a pure chemical combonation of two or more elements in a fixed ratio.
3. What is the difference between NaOH(s) and NaOH(aq)?
NaOH (s) is a solid and NaOH (aq) is aqueous, meaning that it dissolves in water.

Chapter 7 Practice Problems
1. What is a chemical reaction?
A chemical reaction takes place when one substance is made into another by adding liquid or heating it. Evidence of chemical reactions include color change and gaseous substances.
5A. Vinegar is a liquid and baking soda is a gas so the combonation of the two creates a liquid and carbon dioxide gas.
5B. Yes, a chemical change occurs because the substances start as a liquid and a solid and end as a gas and a solid.
5C. The sodium starts in baking soda and then dissolves into the liquid.

Chapter 9 Practice Problems
1. Reactivity,size and valence electron number.
2. Carbon and Silicon are more similiar than Nitrogen and Oxygen because carbon and silicon are in the same family whereas nitrogen and silicon are not.
5A. CaSO4
5B. The sulfer would be because it has a higher mass than oxygen.

Chapter 10 Vocab:

Atomic Mass: mass of a single element
Atomic Number: number of protons in an element's nucleus
Reactivity: describes whether or not an element will combine with other substances and the speed at which it takes place
Group: vertical column in the periodic table
Period: horizontal row in the periodic table
Alkali Metals: elements in Group 1A
Alkaline Earth Metals: elements in Group 2A
Halogens: elements in Group 7A
Noble Gases: elements in group 8A, non reactive
Main Group: 1A to 8A
Transition Metals: 1B to 8B
Lanthanides and actinides: two rows places seperately at bottom of table

Practice Problems
1. Reactivity increases as you go down group 1A (Alkali metals)
2. Radium and Barium
6. A, B, D, E