Chemical Reactions Lab

Today in Chemistry we performed a lab that had 11 different experiments that had to be performed to show us the different types of chemical reactions that occur. There are three major indicators that tell us if they are true chemical reactions, which include: a precipitate forming, color change and the appearance of bubble/fizzing. During each mini lab at least one of each indicators was seen, for example me and my partner performed reactions 5 and 8 which was assigned to us by our teacher. Reaction number 5 resulted in turning a milky white, became increasingly hot and had big bubbles that kept fizzing out and in reaction number 8 it turned a bright yellow color. I believe that the products of reactants can be predicted because the atoms in the reactants are the same, so the outcome will always be the same.The reactions were divided up into five sections: Section 1 (Reactions 1 and 2); Section 2 (Reactions 3 and 4); Section 3 (Reactions 5 and 6); Section 4 (Reactions 7, 8 and 9); and Section 5 (Reactions 10 and 11).

This was done based on similarity:

Section 1: Two reactants that produced one product.  Ex: 4Fe+302=2Fe203                                                                                           Section 2: One reactant that produced two or more products.  Ex: 2H202=2H20+02                                                                                 Section 3: One element or ion is replaced by another element/ion in a compound.  Ex: Zn+Pb(NO3)2=Pb+Zn(NO3)2                               Section 4: Two compounds exchanged their elements/ions for those of the other compound.  Ex: Pb(NO3)2+2KI=2KNO3+PbI2               Section 5: Combustion. Ex: CH4+O2=CO2+2H2O

Here are the balanced chemical equations for the 11 chemical reactions:

1. 4Fe(s) + 3O2(g) –> 2Fe2O3(s)

2. CaO(s) + H2O(l) –> Ca(OH)2(aq)

3. 2H2O2(l) —MnO2–> 2H2O(l) + O2(g)

4. 2NaHCO3(s) –> H2O(l) + Na2CO3(s) + CO2(g)

5. Ca(s) + 2H2O –> H2(g) + Ca(OH)2(aq)

6. Zn(s) + Pb(NO3)2(aq) –> Pb(s) + Zn(NO3)2(aq)

7. Na2CO3(aq) + Ba(NO3)2(aq) –> 2NaNO3(aq) + BaCO3(s)

8. Pb(NO3)2(aq) + 2KI(aq) –> 2KNO3(aq) + PbI2(s)

9. CaCO3(s) + 2HCl(aq) –> CO2(g) + H2O(l) + CaCl2(aq)

10. CH4(g) + 2O2(g) –> CO2(g) + 2H2O(g)

11. 4C2H5O2(l) + 9O2(g) –> 8CO2(g) + 10H2O(g)

Image

 Ca(s) + 2H2O –> H2(g) + Ca(OH)2(aq)

Image

Pb(NO3)2(aq) + 2KI(aq) –> 2KNO3(aq) + PbI2(s)

Sources:

Lab Notebook/Notes

Lab Results

In Class Discussion

3 Questions Blog-4/11/14

1. What tasks have you completed recently?

Recently, I have planned out all my classes for next year in order to make sure I am on the right path and will allow me to succeed. I have also taken the ACT test this Saturday for college! In my chemistry class we have completed our test about stoichiometry and limiting reactants.

2. What have you learned recently?

I have learned that studying is very essential and will help you so much when it comes to tests, my studying prepared me for my ACT test and my chemistry test. Also I have learned that it’s okay to make mistakes as long as you learn from them and really try hard to re correct your error.

3. What are you planning on doing next?

I am planning on staying on top of all my school assignments, test and activities in order to achieve my goal of having all A’s in all my classes by the end of this year. I am also going to complete all my National Honors Society volunteer hours by committing my time to the Soup Kitchen and recycling days at school.

White Powder and Unknown Liquid

Yesterday and today in my chemistry class we did a mini lab that experimented with the reactions of combined white powders and unknown liquids to release a gas. We performed three different tests with three different combinations together. The first test we did was with vinegar and sodium bicarbonate which resulted in lots of fizzing and bubbling; creates gas. We used 0.78 grams of sodium bicarbonate and 2 fingers of vinegar which resulted in the production of 0.37 grams of gas. Test number one and two had the result of always being a 1:1 molar ratio which means for every 1 mole of powder used, there should be one mole of gas produced. For test number three is not like the other two because we had to balance the equation by putting a 2 in front of the NaHCO3 and the CO2 which had caused it to become a 2:2 molar ratio. There is a molar relationship between these two substances because you can always determine the amount of gas produced by certain amounts of solid, which is known as the line of best fine, if you have the balanced equations and molar masses. A solid to gas ratio would apply to any and/or all chemical reactions because the only factor in the ratio of gas produced is the type of solid in the reaction. This experiment overall was a very efficient way to help us learn the lesson of the mole and to be introduced to stoichiometry.

Sources:

Class Notes and Class Experiment

Image

Image

Image

 

3 Questions Blog- 3/28/14

1. What tasks have you completed recently?
Recently, I have gone to the 2014 State Spirit Championship with my cheer team and came out with the runner-up trophy in our Co-ed division. I also have completed the NMSBA testing week that is required and I have completed Placement #1 and #2 for chemistry that was due over spring break.

2. What have you learned recently?

These past two weeks have taught me so much about life and how short and beautiful it can be. At the beginning of spring break, my friend was in a really bad car accident and in the end she was okay but you never know how precious time is until you can no longer spend another second with them. This taught me to value everyone and to never leave something unfinished because you never know when something can be taken from you. 
3. What are you planning on doing next?

Next I plan on staying on top of all my classes since it is a brand new semester. I am all rested up from spring break and I am ready to attack all my new obstacles that are thrown my way for the rest of the school year. I will stay organized and study harder in order to try and get all A’s in my classes.

3 Question Blog-3/14/14

1. What tasks have you completed recently?

Recently I have completed a Frankenstein Essay for English about ambition and have watched several movies for AP US History for extra credit. In chemistry, we have recently experimented with moles and empirical formulas as well as molecular formulas. We have also completed a Beans in a Pot Exploratory Lab which we did to help us learn exactly what a mole was representing and how it worked, or how it is used.

2. What have you learned recently? 

In English we have been learning about the Renaissance era and Macbeth; in AP US History we have been learning about pre-war and World War II and the impact it had on our country. In chemistry, I have been learning about the concept of the mole and how to solve molecular and empirical formulas.

3. What are you planning on doing next?

I am planning to further my knowledge on the mole by completing my glog on mole day and I am preparing and planning to try and do my best on the NMSBA testing that is happening all next week.

The mole… In all it’s glory

The most common way to measure chemical substances is through moles . . .Well no, not that kind of mole . . . a chemical mole is a unit of measure, just like a gram or an ounce. It is used internationally so that all chemists speak the same measurement language. The mole was invented because, well, it made sense. Scientists were having a hard time converting between atoms of an element and grams of an element, so scientists came up with a “mole” of substance, which is defined as anything that has 6.02×1023 particles in it.You might recognize 6.02×1023 as Avogadro’s number; this number is used as a constant throughout chemistry, and here we’re going to use it to define the mole. Usually, moles refer to particles that make up a certain amount of an element, and we use moles to measure how much of a substance is reacting in a chemical equation. However, you can also measure other things in moles—for example, a mole of horses would be 6.02×1023 horses . . . which is actually quite a lot. When you think about a mole as 602,000,000,000,000,000,000,000 horses, it seems like way too big of a number to be describing something that fits in a beaker in the chemistry lab! However, because atoms are so small there are bunches of atoms in everything we’re measuring. Therefore, a mole is actually a very appropriate way to measure chemical substances.

20140313-150148.jpg

Beans in a Pot~Exploratory Lab

Today in Chemistry we had 5 different types of beans, each in groups of 50, and found the masses of them all. We had the black beans, lima beans, kidney beans, lentil beans and garbanzo beans.  Once we found the masses of each we decide the smallest mass in the lab which was the lentils, we calculated the relative masses. To get relative masses you must take the masses of each sample of beans divided by the mass of the lentils. After we found the relative masses we used our triple beam balances to find out how many beans were in a “pot”, this means how many beans can fit into the relative mass. The pot is a model of a mole because we can now use it to determine the mass or number of beans in any amount or mass of beans. The relative mass used for that of a mole is that of hydrogen, the lightest element. Below are my group’s results that include the bean type, mass of the 50 beans, the relative mass, rank and the number of beans in a “pot”:

Image

 

Image

 

Image