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Reactions in Our World Lab Report Instructions: In this laboratory activity, you will be comparing chemical reactions to nuclear reactions by observing chemical phenomena in action. To prepare for your observations and data collection, you must complete the pre-lab activity worksheet that goes with this lab. Otherwise, you will not have the chemical equations you need to match each chemical reaction. Fill in each section of this lab report and submit it to your instructor for grading.

Title: Reactions in Our World

Objective(s): To compare the chemical and nuclear reactions by observing the chemical makings in an online lab.

Hypothesis: The reactions between two different types of chemical compounds will vary, taking into consideration their own chemical makeups and properties. 1. You will complete your hypotheses using the chart below and the balanced equations from your pre-lab activity. In each row, predict the reaction type(s) for each chemical reaction. Reaction type options are synthesis, decomposition, single displacement, double displacement, acid-base reaction, combustion, and oxidation-reduction. Some reactions can fit more than one type of reaction. Chemical Reaction Iron and copper (II) sulfate solution Lead (II) nitrate and potassium iodide solutions Magnesium metal and hydrochloric acid solution Electrolysis of water Burning magnesium

Procedures:

Prediction of Reaction Type I predict the reaction between iron and copper sulfate will yield a single displacement reaction/s. I predict the reaction between lead and potassium iodide will yield a double displacement reaction/s. I predict the reaction between magnesium metal and hydrochloric acid will yield a single displacement reaction/s. I predict the reaction between oxygen and hydrogen will yield an oxidation reaction/s. I predict the reaction between magnesium and heat will yield a synthesis reaction/s.

Access the virtual lab and complete all sections of the experiments. A summary of steps has been provided for you. List and explain your controlled variables, independent variable, and dependent variable for this lab. Materials: Reactions in our World Virtual Lab Variables: List your controlled variables, independent variable, and dependent variable for each experiment in the chart below. Remember, controlled variables are factors that remain the same throughout the experiment. An independent (test) variable changes so that the experimenter can see the effect on other variables. The dependent (outcome) variable will change in response to the test variable. Chemical Reaction Iron and copper (II) sulfate solution Lead (II) nitrate and potassium iodide solutions Magnesium metal and hydrochloric acid solution Electrolysis of water Burning magnesium

Controlled Variables Iron Lead

Independent Variable Iron Lead

Magnesium metal Hydrogen Heat

Magnesium metal Hydrogen Heat

Dependent Variable Copper Potassium iodide Hydrochloric acid Oxygen Magnesium

Summary of Steps: 1. Iron and copper (II) sulfate solution Fill a small test tube halfway with copper (II) sulfate solution. Add a 2.0-gram iron rod to the solution and observe the reaction. 2. Lead (II) nitrate and potassium iodide solutions Pour about 2.0 mL of lead (II) nitrate into the test tube. Add 5 to 10 drops of potassium iodide solution to the test tube and record your observations of the reaction. 3. Magnesium metal and hydrochloric acid solution Place one scoop of magnesium turnings into the test tube. Add hydrochloric acid slowly and observe the reaction. Next, place a burning splint near the mouth of the test tube to test for the presence of hydrogen gas. 4. Electrolysis of water Use a U-tube with electrodes at each end, connected to a battery. Fill the U-tube

with water. Turning on the battery, observe the results at each electrode. Next, test for hydrogen and oxygen gas produced at each end of the tube. 5. Burning magnesium Place magnesium ribbon in a clean crucible (on a clay triangle above a Bunsen burner). Heat until the magnesium begins to burn.

Data: Complete a data table that includes reaction observations, balanced equation (from the pre-lab worksheet) identification of reaction type (single replacement, double replacement, synthesis, decomposition, acid-base, oxidation-reduction, or combustion) for each experiment in the lab. Chemical Reaction

Example:

Observations

Reaction Type

Balanced Equation

Violent reaction, sodium flames in solution

Single replacement, combustion reaction

2 Na + 2 H2O ---> 2 NaOH + H2

The iron changed in color immediately, a brownish color.

Single Displacement

Fe(s)+

Sodium and water Iron and copper (II) sulfate solution

CuSO4(aq)FeSo4(aq)+ Cu(s)

Lead (II) nitrate and potassium iodide solutions

The solution got displaced to the bottom of the test tube and also changed to a thick yellow substance.

Double Displacement

Pb(NO3)2+KI

Magnesium metal and hydrochloric acid solution

The magnesium in the test tube formed bubbles.

Single Displacement

Mg+2HCI

Electrolysis of water

Small bubbles appeared, almost as if it was at a simmer heat point.

Decomposition

2H20 + 02(g)

Burning magnesium

Magnesium when heated showed both red and white flames.

Synthesis

2Mg+02 Mg0

Conclusion: Write a conclusion statement that addresses the following questions:   

Summarize your observations of each reaction. Based on the products made, were your predictions of chemical reaction type correct? Some of the reactions you conducted can be categorized as more than one type of reaction. Which reactions are these, and what are the types of reactions? How do you think the investigation can be explored further?

Through the several different reactions between several different substances that I observed, there were two types of main reactions that were formed for the burning of magnesium, synthesis and combustion. Because the magnesium burning can be classified as either synthesis or combustion, my predictions were true. One could further explore this type of experiment by bringing more factors into it. There are several other types of reactions in our world that we can experience, observe and further learn from. For example, there could be more reactions added that would form combination, since we didn’t experience one, or more of decomposition of synthesis reactions in order to see how different components react differently.

Post-Lab Reflection Questions Answer the reflection questions using what you have learned from the lesson and your experimental data. It will be helpful to refer to your chemistry journal notes. Answer questions in complete sentences. 1. If you were to measure the mass of magnesium and hydrochloric acid before combining them in the test tube, how would that mass compare to the mass of reactants left in the test tube after the reaction? Explain your answer and how it corresponds to the law of conservation of mass. If you were to measure the mass of magnesium and hydrochloric acid before mixing them in a test tube, generally speaking the masses left after the reaction should be the same as before they were placed into the testing tube. Due to the Law of Conservation of mass, which was learned constantly throughout the modules, the masses would stay the same throughout the experiment because even when matter is changed, the total mass remains the same. 2. In what other ways could you test your predictions to confirm their accuracy? There are some other ways to go into detail on whether or not the predictions made before the experiment are accurate. A much complex way would be to take into consideration the balanced equations of each reaction and compare them to expose what type of reaction formed. Another way, which follows the rules of science to make sure evidence is entirely accurate, is repeating the experiment to observe again if the same results and characteristics of the substances are shown. 3. How do the chemical reactions in this lab activity compare to nuclear reactions, such as fission and fusion?

It is apparent that nuclear reactions are much larger and serious than the chemical reactions experienced in this lab that were much simpler. When nuclear energy is released from a given reaction in an experiment, the nuclei release very quickly and powerfully in large amounts to create a stronger and complex reaction. Compared to a simple combustion reaction, which releases energy very slowly and timely....