Monday, October 18, 2010

We started our lovely Monday afternoon off with the stamping of our homework (Periodic Table and Periodicity Webquest and the Alien Lab). Make sure Mrs. M stamps it if you were absent.

Make sure to grab the new sheets from the bin (Anatomy of the Periodic Table 1, 2, & 3; Metal Reactivity: Periodic Trends Lab all 4 sheets). Put all in your journals. We went over the Webquest and answered questions that were asked. We then transitioned into today's lesson: metals, nonmetals, and metalloids. We started off in our Metal, Nonmetal, Metalloid sheets, page 2. We filled out #3, classifying metals, nonmetals, and metalloids:

METALS:

• malleable
• shiny
• good conductors of electricity

NONMETALS:

• crush (brittle)
• dull
• bad conductors of electricity

METALLOIDS

• have properties of both metals and nonmetals

We continued onto our chart labeled with the elements A-G. We corrected a few mistakes in the conductivity column (element B and C DO NOT conduct electricity). Mrs. M then put the elements in a tray, and added HCl and CuCl2 to two samples of each. We then recorded the results. Here is the information you should add to your chart:

• Elements F and G reacted with HCl, while the rest did not.
• Elements A, D, F, and G reacted with CuCl2, while the rest did not.

After completing the chart, we moved on to the last portion of our lesson. Mrs. M showed us a video of the reactivity trends of metals in groups and periods. We filled out Part A while we watched the video. In the video, we saw reactions of the Alkali metals lithium, sodium, potassium, rubidium, and cesium when they were dropped into water. Here were our observations:

PART A

• Li- floats, gives off Hydrogen gas, fizzes in water
• Na- floats, gives off Hydrogen gas, fizzing is much more vigorous
• K- gives off heat so hot that it lights the Hydrogen gas on fire creating a flame (same reaction as above except more vigorous)
• Rb- same reaction, except more vigorous than K, Hydrogen caught on fire, more intense
• Cs- most intense, "light show", breaks glass container that it was being tested in

PART B

After filling out the data from above, we continued onto Part B, as Mrs. M demonstrated. We filled out question 1 by describing what the metal samples looked like:

• Mg- silver, shiny, thin strip
• Al- silver, shiny, round pebble-like shape

Next, she lit a Bunsen burner, warned us about NOT looking directly at what she was about to do, and WEARING HER SAFETY GOGGLES, held a piece a Mg over the flame and caught the "ashes" in a container. The Mg gave off a bright light and ended quickly, leaving behind a chalky, white substance in the container. These "ashes" are the product MgO, made from the reaction of Mg and oxygen while burning.

We moved onto testing the next metal, Al. Mrs. M used Al this time instead of Mg and we saw a different reaction. The flame turned bright orange/red, and the "ashes" did not change much besides coming dull and a bit less malleable. These "ashes" are the produt of Al2O3, made from the reaction of Al and O2 while burning.

We answered the next question, Do the metals burn the same? Compare the two:

no, they do not burn the same. Mg had a product that was chalky and white, while Al had a product that was dull and less malleable than before.

This was all for today, as the bell cut us short.

HOMEWORK:

• WebAssigns (you're favorite)
• finish Metal, Nonmetal, Metalloid pages