Blog Question

I understand that the periodic table is a table of chemical elements in order by atomic number in rows so that elements with similar atomic structures appear in vertical columns. Also similar chemical properties are in the same columns. The elements with a different number or neutrons from protons and electrons are isotopes. The very right column consists of noble gases that do not react and the very left column consists of elements that have high reactions.

HW #2

2SAS #13-25:

13. a) Row: period    b) Column: group

14. Sodium (N) and Potassium (K). 

15. (a) The noble gases are located in column 18.    (b) They are all odorless.    (c) They do not chemically react.

16. (a) MgF2    (b) GaP

17.  69 degrees C. 

18. I think the boiling point of Chlorine is lower because it has a smaller atomic mass.

19. A. C

      B. N

      C. 20

      D. 20 

      E. Pt

      F. 78

      G. 92

      H. 92

20. (a) 4 protons, 4 electrons, 5 neutrons   (b) 7 protons, 7 electrons,7 neutrons   (c) 10 protons, 10 electrons, 10 neutrons

21. The lead atom must have gained two electrons in order to make the ion because you can not loose or gain protons.

22. A. Carbon: 12.01

           Nitrogen: 14.01

           Calcium: 40.08

           Platinum: 195.08

           Uranium: 238.03 

      B. Platinum and Uranium both have two isotopes. 

23. No, this is not enough to justify the claim of the discovery of a new element because you do not have enough information to determine the elements physical or chemical properties.

24. The electron 1/2000 the moss of the proton and neutron.

25. 24- 24, 12, 12

      25- 25, 12, 13

      26- 26, 12, 14 

Metals or Non-metals Lab Report

Metal or Nonmetal

7/9/13

Georgie Dorfman, Ben Cohen, and Charlie Dorfman

Dr. Foreman

Abstract:

My group and I identified the unknown elements as either a metal, metalloid, or a nonmetal. We did this by preforming 5 different tests. We tested for physical properties or chemical properties. To test the physical properties we recorded the appearance of the elements (luster or dull) and we crushed the elements with a hammer to see if the element were brittle (break), or if they were malleable (would not break). To test for the chemical properties we tested for the presence of conductivity and for the recording of reactivity with hydrochloric acid and copper chloride.

Significance of lab:

This lab gave me a better understanding on how to distinguish the difference between metals, metalloids, and nonmetals. I learned that you cannot distinguish between metals and non-metals by judging its appearance. There are important tests that have to take place to test between the two. 

Purpose:

The purpose of this lab is to test un-known elements and determine whether each element is a metal, metalloid, or a nonmetal.

Procedure:

1. Create a data table including six columns, including the elements and the properties we are testing for

2. Record the appearance of each element 

3. Use an electrical conductivity apparatus and touch both electrodes to the element sample

4. Record if the element is a conductor or a nonconductor

Non-conductor

 

Conductor

5. Gently tap each element with a hammer

6. Record if the element is malleable (flattens, but doesn't shatter) or brittle (shatters into pieces)

Brittle

Malleable

7. Reactivity with copper chloride:

-Label seven wells in a well-plate A-G

-Put a sample of each element into each well

- Add 15-20 drops of 0.1 M copper chloride to each sample

-Allow the sample to sit for 5 minutes

-Observe and record a change in the sample's appearance and see if the elements reacted with the copper chloride

reaction with copper chloride

8. Put the well plate to the side
9. Get a new well plate
10. Reactivity with acid:

              -Label seven wells in the clean well-plate A-G

              -Place a sample of each element into a separate well

              -Add 15-20 drops of 0.5 M HCl to each sample

-Allow the sample to sit for 5 minutes

-Observe and record if there is a formation of gas bubbles and if there is a reaction with the hydrochloric acid

reaction with hydrologic acid

-Discard both well-plates

-Wash your hands thoroughly 

Results:

My group and I had a hard time deciding which elements were metals, nonmetals, or metalloids. From our five observations, it was easy to detect if the elements were either metals or nonmetals because they have very distinct results. Identifying if each element is a metalloid was more difficult because metalloids are a mixture of both metals and nonmetals, so a slight mistake in a step could lead to the belief that the element is a metalloid. This was difficult because some elements conducted electricity, but could easily shatter like elements D and G. Some elements could not conducted electricity, but were malleable at the same time like element A. Comparisons like this gave us a hard time. With all these different results, my group and I finally were able to decide which unknown elements were metals, metalloids, or nonmetals. We came to the conclusion that elements A, C, and F were metals, elements B, D, and G were metalloids, and element E was a nonmetal.

Class aggregated data:

There is a variation in results. For element A, most groups concluded that it was metal, while the group Carbon concluded it was a nonmetal. For element B, there was an even number of results of metalloids and metals. For element C, most groups concluded that the element was a metal. For element D, the results varied between metals, nonmetals, or metalloids. For element E, most groups concluded that the element was a nonmetal. For element F, all groups concluded that this element was a metal. For element G, the results varied between metals, metalloids, and nonmetals. With the confusion of metalloids, the results varied because of the close difference it makes.

Lab Questions:

1. The physical properties tested were the appearance and the crushing of the element. The chemical properties were conductivity and the reactivity with copper chloride and hydrochloric acid.

2. The first group unknown elements are the metals. This group consists of elements A, C, and F. The second group of the unknown elements are called the nonmetals. This group consists of one element E.

3. The elements that could fit into either group are elements B, D, and G. These elements are metalloids. These elements look luster and conduct electricity, but they are brittle and don't react with the two solutions. And some of these elements may look dull, but actually conducts electricity. This makes them metalloids.

4. The metals are elements A, C, and F. The metalloids are elements B, D, and G. The nonmetal is element E.

HW #1

2SAS (p.130) #1-12

1.

a) physical property   b) chemical property   c) chemical property   d) physical property

2. 

a. physical property   b. physical property  c. physical property   d. chemical property

3. 

a. chemical change   b. chemical change    c. chemical change    d. physical change

4. 

a. chemical change    b. chemical change    c. physical change   d. physical change

5.
   4a. It is a chemical change because the apple that was left out and turned brown due to the air chemically changing the appearance of the apple.
   4b.It is a chemical change because flashlight batteries contains electricity, and when the battery looses it's charge it looses energy and can not function anymore.
   4c. It is a chemical change because the clothing looks the same, but the chemicals in dry cleaning remove the oil.
   4d. It is a physical change because nothing was added to the salad dressing to change it's content. Just over time the salad dressing separates, but it is still the same material when you shake the bottle.

6.
   a. Mix all the ingredients together in a bowl; including milk, eggs, sugar, flour, and chocolate chips. Then in small amounts put the cookie batter on the baking sheet, and then place the sheet in the oven. When the cookies are golden, remove the it from the oven, and let them cool.
   b. Mixing all the ingredients together is a physical change because the material stays the same, it is just looks different. Placing the cookies on the baking sheet is a physical change because it is the same material, just a different shape. Baking the cookies is a chemical change because the cookies will permanently be made into a solid. Taking the cookies out of the oven is a chemical change because the change in temperature is hardening the cookie.

7. 

a. metal    b. nonmetal    c. nonmetal    d. metal

8.
  a. tungsten: metal  b. antimony: metalloid  c. krypton: nonmetal  d. sodium: metal

9. Two metalloids are: silicon (Si) and germanium (Ge)

10.
   a. Iodine is a nonmetal, so it would shatter.   b. Zirconium is a metal, so it would flatten, but not shatter.   c. phosphorus is a nonmetal so it would shatter.   d. nickel is a metal so it would flatten, but not shatter.

11. They easily break because they are brittle and they can not conduct electricity so they would not be able to transmit electricity.

12. If they are shinny (luster), malleable, and if they are not brittle like nonmetals.

Blog Question

The most important idea I have learned about in Unit 1 was the foul water testing. This was the basis for everything we learned in this unit. I learned how to clean water in one day and I never imagined that I would ever learn how to clean water.

What Killed the Fish

Results:

Scenario 1:

In May, June, July of every year there is an increase in the amount of rainfall. However, this year in August there was a sudden change in the amount of water that appeared. There was much higher water flow due to the abnormal amounts of rainfall. The fish died in scenario 1 because of the excess in pesticides. The reason this is weird is because there was no un usual amount of rainfall, water flow, or dissolved oxygen in the month of August. The pesticides were present in September and it too a week to kill the fish in August. This is because it took a week for the dangerous amount of pesticides to flow into the water.

Scenario 2:
In May, June, and July there is still excessive amounts of rainfall appearing in these months. Because of these huge amounts of water, this caused much of the nitrate to flow into the water.  What killed the fish in scenario 2 was the extreme amount of nitrate. This could have causes the fish kill because nitrate could prevent oxygen from being carried throughout the fish's body causing bubbles to occur in their blood.

Blog Question

We drink bottled water because tap water has been cleaned in a municipal water treatment plant and it still contains gasses and minerals while bottled water is naturally more pure due to the hydrologic cycle, which is our cleanest source of water.