3 questionsss

1. Recently we have learned about electron energy and light.

2.We completed a POGIL, lab, and worksheets in order to enhance our studies. We have also taken many notes and had class discussion.

3. I plan to review past material and this recently learned material over christmas break! :)

A Sticky Situation: Chocolate Gum!

A substance's ability to dissolve in a solvent at a given temperature is its solubility. For example, one could see solubility of the solvent oil in the solute water. The oil does not mix with the water, but stays on top of it. However, one could dissolve salt into water.  Solubility differs from solvation, in that solvation is the process of attraction/association of molecules of a solvent with the molecules or ions of a solute. Solubility arose in the Sticky Situation lab. 

A Sticky Situation: Chewing Gum and Solubility lab tested the solubility of various components of chewing gum. There were many different tests; water and sugar, water and oil, oil and sugar, gum and saliva, gum and water then oil, and gum and chocolate with saliva. The results of the liquid mixtures were typical. Whenever the gum and water were mixed, the water dissolved the sugar coating of the gum. When put in oil (with some poking), the gum eventually broke down. In chewing both the gum and chocolate, an ingredient in the chocolate disassociated the gum. 

The different disassociation of gum ultimately have to do with the intermolecular forces with in the gum base polymer. Intermolecular forces are the attractive or repulsive forces between atoms. The forces outside of the molecules must be stronger than the intermolecular forces in order for disassociation to occur. 

In order for one substance to dissolve another there must be similar intermolecular forces. This concept can be summarized by the term "like dissolves like." This concept was observed in the lab in mixtures like the sugar and water. 

3 Q's!!!

Of course we've done labs as always, but we've also taken a lot of notes?! It has been extremely helpful :) Oh and I almost forgot we've done my favorite, online homework!  -_-

We haven't really learned anything lately sooo...
 Just kidding! We've learned SO much it is crazy. We completed a whole chapter on gas laws, PV=NRT!!! We also moved on to learn about inter molecular forces.

I am planning on re-quizzing, getting tutored, asking questions, and actually reading and using the textbook before the big test!!!! :)

3 Questions!!!

1. We've done so many things!! Online homework, new labs, gas laws, ionic equations, solutions, I could go on forever...

2. I am in the process of learning PV=NRT, mole fractions, and the applications of gas laws. 

3. Now I'm trying to maintain a positive attitude, and plan on working very hard in order to fully understand the applications of gas laws and other materials.  

What's up! 3 questionssssss

1. I have been beyond stressed. I am like drowning in chemistry:( BUT I have been able to keep up and complete my tasks. We have done a lot of labs!!! These labs have had to do with solubility and molarity. We had a huge cation and anion lab and completed a quiz! yay :)

2. I feel like I am overloaded with information. There are a couple of things that have stuck like; molarity, solubility, disassociation, and solvation!!! 

3. Next, I'm going to work harder than I have ever worked to get a grasp on everything we are learning, and hope for the best!

TITRATION LAB

We completed a titration lab! The purpose of this lab was to determine the molarity of a sulfuric acid in NaOH. First we began the procedure by placing 20 mL of diluted sulfuric acid into a flask. We then added three drops of the indicator Phenolphthalein, to the solution. We then placed a small magnet in the flask to secure it to a magnetic plate. The magnetic plate constantly stirred the solution. Above the flask, we placed a buret with NaOH and slowly added in the NaOH. The indicator that we added turned light pink, allowing us to know the acid had been neutralized.

The added NaOH turned the indicator pink but quickly dispersed. This picture was taken while the NaOH was mixing. The final color was not this dark.

The color of pink desired was light pink, not dark pink. We obtained the light pink color in two trials in which we added 18.4 mL of NaOH. 

   

Based on our calculations we used .0184 mol of NaOH. We multiplied the mole ratio of H2SO4 to NaOH, getting the number .0092 moles of H2SO4. We then divided by the whole, .020L to get the molarity .46M  of H2SO4.

Solubility Lab and Rules! :D

A couple weeks ago we did yet another lab, yay! In this specific lab, the materials included different solutions containing either cations or anions. We then combined the different solutions to determine solubility. I put my observations in a chart. It's a little messy but here it is;

From the results, we were able to conclude solubility rules about the anions and cations.

Anions: 

• NO3 is ALWAYS soluble
• Cl is ALWAYS soluble (except for Pb and Ag)
• Po4 is usually solube (except for alkaline metals)
• SO4 is always soluble (except for Pb)

Cations:

• All alkali metals are soluble (Na, K, NH4)
• Silver is insoluble (except bonds with Sulfate and Nitrate)
• Lead is insoluble (except bonds with Nitrate)
• Ammonium is ALWAYS soluble

Electrolytes and Solutions!

Learning Objectives!

• Review definitions of solution and electrolytes
• Can you create a particle diagram of a salt solution?
• Can you create two different concentrations of salt solutions and qualitatively demonstrate this difference?
• Can you mathematically show the difference in concentration and provide the calculations to justify it?

A solution is defined as a homogeneous mixture of 2 or more substances. An electrolyte is a substance that disassociates into ions when dissolved in water. 

An example of a solution would be salt water. 

We qualitively demonstrated the difference between two different salt solutions. These solutions contained different amounts of salt and water. One solution consisted of 100 mL of distilled water and 2.5 grams of salt. The other solution had a massive amount of distilled water at 600 mL and a mere .1g of salt. 

We then tested the electrolytes in the water by seeing if the solution would conduct electricity and how much of it. We used this scary looking thing with two prongs and a light bulb attached. The results produced are in the pictures below. 

Beaker with 100 mL of distilled water and 2.5 grams of salt.

This beaker obviously contained the 600 mL of water and .1 grams of salt! This solution was our attempt to create tap water. It was a bit difficult to create the same amount of light that the tap water did. You can compare our light to the tap water's light with the picture below!


                            Original 

Here is how we calculated our data to show the difference in concentration: REMEMBER WE WANT TO GET TO MOLES TO OBTAIN MOLARITY. MOLARITY= MOL/LITER

DIFFERENT MOLARITY = DIFFERENT CONCENTRATIONS 

Three Questions!!!!!!

We have completed SO MUCH recently. We have done several labs, some on law of conservation of mass, limiting reagents, and green chemistry! We have done several quizzes as well. 

I've learned a lot including percent yield, limiting reagents, and combustion analysis. I am in the process of completely understanding stoichiometry and green chemistry. 

Next I plan on retaking quizzes, reading through my notes, and other ways of studying to reinforce this material! :)

Electrolysis of Water Lab

•  What is the balanced chemical equation of this experiment?
•  Is there qualitative evidence to support the balanced reaction?
•  Could you collect quantitative data to 'prove' the balanced equation 
•  Can you draw the particle diagram?

      Through a simple and fast procedure, we were able to view the separation of both 

hydrogen and oxygen within a baking soda mixture. In order to examine this separation,we filled two test tubes with the baking soda and water solution. We had a cup with two thumbtacks in which we placed each test tube over, and quickly there after filled the cup with the solution. We then placed the cup on a battery with each thumbtack on the positive and negative side of the battery. The setup and and beginning reaction looked like this:

 In this electrolysis of water lab, the production of hydrogen and oxygen can be represented through  the decomposition reaction equation; 2H2O----> 2H2 + O2. This balanced chemical equation can be supported by the quantitative evidence. Quantitative data in this lab supports the Law of Conservation of mass. In order to record this data one would mass the solution before and after the reaction. This law is proved by the equation produced, and by the particle diagram below.

Qualitative data was also observed in order to prove the balanced equation. This data includes; the examination of bubble production rate within each tube. We observed the rate of bubble production in one tube, which was significantly faster than the other. Thus further proving the separation of the hydrogen and oxygen gases. 

 An indicator was  also added to the substance. This gave us, the observers, another view as to     what was happening with in thee substance. With the addition of the indicator, the colors in the tubes began changing. One tube had more of a yellow tint, while the other had more of a blue color thus indicating a divergence of an acid and a base in the substance.

                                                  

Composition of a Hydrate Lab

        We performed this lab in order to determine whether a hydrate was a pure substance or a mixture. In order to determine the composition of the hydrate, we used a specific and significant technique. This technique was the use of heat to determine whether or not the substance's mass remained the same or varied. If the substance had resulted in a significant loss of mass, with an erratic percent composition of water,  one could conclude that the hydrate was a mixture. This conclusion would be valid because, a mixture is made up of more than one pure substance. Each pure substance's components have different properties. Opposed is a pure substance, which contains only one type molecule. This means that the substance maintains a constant composition. If the hydrate was a pure substance, when it was heated it should have resulted in no loss of mass or a consistent loss of water composition percentage. We used this percent composition in mathematically proving that the hydrate was a pure substance. In order to prove our conclusion valid, the percentage we obtained must have been in range of 48.8%. Our percentage amounted to 47.7%  meaning a minuscule percent error and a valid result.