Chemistry Review #9

9.  The octet rule is a rule which states that elements like to have their valence shells completely full, which gives them the same composition as a noble gas. 

a.  In order for an element to achieve an octet and mimic the composition of a noble gas, the valence shell must be full.

B  Elements with only one shell, the rule of the first shell of electrons or s orbitals, defies the octet rule.  Within this rule, helium, hydrogen and Lithium; helium is content with its two electrons filling the first shell, hydrogen needs to gain one to fill its shell, and lithium also needs to gain one to fill its shell.

c.  Elements in the 3,4,5,6, and 7 periods can expand their octet because their electrons can absorb more energy and move to a higher energy level.   

Iowa Caucus

Mitt Romney beat out Rick Santorum in the Iowa Caucus yesterday, and in the article the author wondered or asked the question why there was no recount.  The author goes on to explain that caucus’ are just to see how each state is going to vote and which candidates are doing well and vice versa; it serves as a guide.  If this is true then there should be no reason for any of the candidates to drop-out, in fact if they are falling behind in the race at this time I would believe that it would give them more motivation and to try to work harder to gain the republican nomination.  Yet, Michelle Bauchmann dropped out of the race losing in the Iowa Caucus.  But for what reason?  Senator John McCain, after placing 4^th in the Iowa caucus, made a comeback and won the Republican nomination back in 2008.  Our representatives, running for Republican nomination, should use this only as a tool and to judge where they are so they can become stronger from it, and nothing more than that.  And if candidates do dropout after just a guideline vote, then how can we expect them to run a country?  When it gets to hard will they quit?  So maybe this is more than just a guideline vote.

Chemistry Study Guide # 21

 21. A. 4  B. 4 C. 3 D. 2 E. 6 f. 6  G. answer is 82450.01 so it is 7 sig figs

Physical and Chemical Properties of Baking Soda

Cameron Laird

Honors Chemistry

Van Buskirk

9/20/11

                                    Physical and Chemical Properties of Baking Soda

Purpose:  The purpose of this experiment is to test the physical and chemical properties of any given household object.  For my experiment, I used baking powder.  So therefore the purpose of my procedure was to test the substance to see how it reacted; to see what were the chemical and physical properties.  In the experiment I specifically tested for color and color change, odor, boiling and melting point, solubility, evaporation, and reactivity with fire, tums, red wine vinegar, tums, hydrogen peroxide, and lemon juice or acid.

Hypothesis: I believe that the baking soda will be soluble in water, will have low boiling point, and a very low melting point.  I also believe that burning the baking powder will give a reaction to being burned, with the red wine, the acid, and the hydrogen peroxide.  Whereas the tum, or Calcium carbonate, will have no reaction.

Materials: Baking powder, ½ Teaspoon, ¼ Teaspoon, 1qt Pot, Spoon, Paper towels, Tap water, Lighter, Red Wine Vinegar, Hydrogen peroxide, Calcium Carbonate/1Tum, Acid/ Lemon Juice, 1 cup measuring cup, Small dish, Freezer, freezer lock baggies.  

Procedure:  1. Add ½ teaspoon of baking powder to the one 1qt pot.  Fill the Pot with ½ a cup of water.  Watch and record

2. Add ½ teaspoon of baking powder to the one 1qt pot.  Fill the Pot with ½ a cup of water.  Put the pot onto the stove and set it to the highest possible heat.  Watch and observe for approximately 30 seconds.  Watch and Record.

3. Take one half of baking powder and wrap it in a freezer lock bag.  Set the freezer on zero and put the baking powder in for 20 minutes.  Rest and let it thaw record your observations.

4. Add ½ teaspoon of baking powder to the one 1qt pot.  Fill the Pot with ½ a cup of water.  Fill the water with a thoroughly crushed Tums.  Watch and Record.

5.  Take a ¼ Teaspoon of baking powder and put it into a spoon.  Take a lighter and begin to burn the Baking powder.  Watch and Record.

6.   Take 3 dishes and label them Acid, Red Wine Vinegar, and Hydrogen peroxide.  Add ½ baking powder to each dish.  The add the Acid, Red Wine Vinegar and Hydrogen peroxide to the correctly labeled dish.  Watch and Record.

Data: The baking powder was soluble.  It did not have an boiling point, and therefore did not evaporate.  The baking powder did have a melting point at 60 degrees C.  No odor was emitted.  The baking powder had no reaction to the fire, as with the tums.  And finally the acid had the highest activity of all of them.

Analysis: The baking powder was soluble for obvious reasons; it has many of the same qualities of salt.  In the way that baking powder acts like salt molecularly, is that is has no boiling point or evaporation.  Also when we added the baking powder to the water it began to bubble profusely.  I boiled the water forever to see if it would evaporate or begin to sizzle, but only the water was, not the baking powder.  The baking powder did however melt fairly quickly after I took it out of the freezer.  Out of the experiments we did, no odor was emitted except for one, but that it when it reacts chemically and not mixed, other than a chemical reaction, there was no odor.  Also with this the color did not change unless it was mixed with something else due to its whiteness.  When we tried to burn the baking powder we tried to burn the bottom of the spoon to get the baking powder to burn but it didn’t so we put the flame on the top, and it only sired it, it had no chemical reaction with the baking powder.  The tums had no chemical reaction with the baking powder, all it did was mix with each other  As for the final four steps, all of these were reactive with the baking powder but not as much as the acid.  As soon as the acid hit the baking powder it was sizzling instantaneously and seemed as if it expanded the baking powder.  In other words it began to bubble profusely.  Also when the acid reacted with the powder, it changed the odor almost to a cleaner odor.  The hydrogen peroxide and the red wine did affect the baking soda but only slightly causing light bubbling.

Conclusion:   In most of the situations, my hypothesis was wrong.  All in all the baking powder was reactance, soluble in water, acid, vinegar, and hydrogen peroxide.  Whereas nothing happened when we light it on fire, added tums, or boiled the pot.  If the pots and other utensils were not cleaned thoroughly there could have been immense mistakes; as wells as adding too much of one chemical or substance which would have over powder the baking soda, not causing the same effect as if we would have added less.