Properties and Changes of Matter PDF

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This report includes data collected from the lab. Grade: A...

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Chemistry Lab Report Experiment 2: Properties and Changes of Matter

February 19, 2021 Spring 2021

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Properties and Changes of Matter Introduction Matter can either be classified as a pure substance or mixture by its competition, as physical or chemical properties, or physical or chemical change. A pure substance will have a fixed composition with known properties and a mixture will be when two or more pure substances are combined. These mixtures are divided into two, homogeneous and heterogeneous. The difference between these two is that a homogeneous mixture will have the same uniform throughout distribution while a heterogeneous mixture, on the other hand, is a mixture that is uniformly distributed throughout. Now, in pure substance, the matter can be also classified into elements and compounds, elements are pure substances that are made up of the same type of atoms, Aluminum for instance. While compounds, on the other hand, are atoms that are made up out of two different elements that are chemically bonded together, an example of this can include water. A physical property can be some characteristics that are shown without changing the identity of a substance meanwhile chemical property will undergo chemical reactions to make new substances. Physical change, on the other hand, will just change their appearances such as in size or state but a chemical change will change the original substance to a new substance with different properties. In this experiment, some of the indicators of chemical change that were observed were the formation of a solid, a gas, a change in color, or a smell. However, some of the objectives of this experiment were to be able to identify matter such as elements, compounds, mixtures whether homogeneous or heterogeneous, physical and chemical properties of matter, as well as physical or chemical changes in compounds. While performing this experiment, there were some hazards and precautions that were handled with care. For example, Iodine was handle because may be combustible at a higher temperature, HCl could cause great damage to skin and

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irritation as well as other chemicals some alcohols that can be flammable, must keep them away from the flame, others can be very toxic, some of this could explode if heated and some are dangerous if exhaled. However, it was important to use a Bunsen burner, and knowing how to work with the fume hood to prevent any hazards. II. Results Analysis Part I 4%NaCl

IV Solution

Aluminum Foil

CaCO3

Soda Bottle

Soda Glass

0.1M CuSO4

Salad Dressing

Matter

Observation

Baking soda

Pure Substance Mixture Element Compound Homogenous Heterogeneous

4% NaCl

Clear Solution

Y

IV Solution Aluminum Foil

Clear Solution Silver Thin Material

Y Y

Calcium carbonate

White Powder

Y

Baking soda

White powder

Y 2

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A bottle of Soda (unopened) Glass of Soda

0.1M CuSO4 Salad Dressing

Brown Liquid

Y

Gas inside because of bubbling

Y

Blue Liquid Food particles of substances

Y Y

Part II A Physical Properties and Changes A. Heating Iodine Crystals (Do this in the fume hood) During

After

Observations heating Iodine Initial matter at bottom of the beaker

Solid

Matter (and state) in the volume of the covered beak

Gas

Name of the process involved

Sublimation

Matter (and state) at the bottom of evaporating dish

Solid

Name of the process involved

Deposition

Classify the type of change

Physical Change

Type of property observed

Physical Property

Part II B solubility of a Solid in Water 3

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a) Iodine Before

?

Observations of Iodine mixed with water Iodine before adding water

orange/brownish substance with black particles

Observation when mixed in water

Orange/brown mixture

Classify your observations (soluble slightly or not)

Slightly soluble

Classify the type of change

Physical Change

Part II B b Sugar

DI Water

+

Sucrose

=

Result After Mixing

Observations of sugar mixed with water

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Sugar before adding water

White Substance

Observation when mixed in water

Sugar was dissolved

Classify your observations (soluble slightly or not)

Soluble

Classify the type of change

Physical Change

Part B c Calcium Carbonate DI Water

+

Calcium Carbonate

= Result After Mixing

Observations of Calcium Carbonate mixed with water Calcium Carbonate before adding water

White Powder

Observation when mixed in water

Cloudy Solution

Classify your observations (soluble slightly or not)

Slightly soluble

Classify the type of change

Physical change

Part II C Solubility of a Liquid in Water DI Water + Liquid

=

Result After Mixing

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Observations of vinegar and oil when mixed with water Vinegar before adding water

Clear Solution

Observation of 1st tube vinegar + water

Clear solution after mixed

Classify your observations (miscible or immiscible)

Miscible

Classify the type of change

Physical Change

Oil before adding water

Yellowish solution

Observation of 2nd tube oil + water

Water went to the bottom while the oil went to the top. Water was denser than oil

Classify your observations (miscible or immiscible)

Immiscible

Classify the type of change

Physical Change

Part II D Melting point determination

Newly inserted capillary tube with Unknown solid

Unknown solid start to melted at 102 oC

Unknown solid completely melted at 106 oC

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Observations Describe your observations in the Mel-Tem

The crystals first liquified at around 102℃

Melting point in ℃ of unknown solid

From 103℃ to 106℃

Identity of unknown Solid

Fructose

Part III A Chemical Properties and Changes A Reaction of an element substance Copper Strip Before Burning

Copper Strip After Burning

Observations before and after burning Observation of initial Copper wire

A solid shiny piece of metal

Observation of Copper wire after heating

Black substance

Classify the type of change

Chemical Change

Categorize the type of process/reaction

Chemical

Part III B Reaction of Solution a) Ionic Compound Reactions with Strong Acid Sodium Carbonate + Hydrochloric Acid

Sodium sulfate + Hydrochloric Acid

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Observations of test tubes #1 & #2 (#1) Sodium Carbonate Solution

White powder

(#1) Sodium Carbonate + HCl

Bubbles

(#1) Classify the type of change

Chemical Change

(#1) Categorize the type of process/reaction

Chemical Reaction Double displacement

(#2) Sodium Sulfate Solution

White powder

(#2) Sodium Sulfate + HCl

Clear liquid

(#2) Classify the type of change

Physical Change

(#2) Categorize the type of process/reaction

Physical Reaction

Part III B. b) Reaction of Iodine Solution with Soluble Starch

Observations

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Iodine reaction with Starch

Slightly orange liquid

Classify the type of change

Chemical change

Categorize the type of process/reaction

Chemical Reaction

A. Data

Summarize important results and refer the reader to the attached datasheet. B. Discussion

PART I

Classification of Matter

In this part of the experiment, the classifications of matter were observed, whether it was a pure substance or a mixture. If it was a pure substance, it was identified whether as an element or a compound, now, if it was a mixture it was identified as heterogeneous or homogeneous, and this was some of the basis that was used in classifying some materials that were given in this experiment, and some of the materials that were classified were 4% NaCl solution, IV solution, Aluminum, Calcium Carbonate, baking soda, an unopened soda bottle, a glass of soda, 0.1M CuSO4, and finally salad dressing. After the classification of matter, it was observed that from the materials that were classified and mentioned above, there was only one element, there were two compounds, four homogeneous mixtures, and two heterogeneous mixtures.

PART II

Physical Properties and Changes

Now in part of the experiment, some subparts needed to be done to explain each of the steps taken to perform an accurate test. The results in “Part II A Physical Properties and changes” of the experiment, the crystals underwent sublimation and deposition. This happened

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because when Iodine was being heated it started to vaporize meaning that it sublimed. Once the gas touched the evaporation dish, it started to turn back into solid, and by doing it, it underwent deposition. These changes can be classified as physical changes because the physical components are changing states and there was also no reaction occurring or any matter changing its composition. Now “Part II B Solubility of a Solid in Water” was divided into smaller subparts as “a) Iodine Solubility”, “b) Sugar Solubility” and “c) Calcium Carbonate Solubility” Before starting it is important to consider that solubility is a property that is referring to the ability of a solute to be able to dissolve in a solvent. However, to be able to determine the solubility of certain solids in liquid, if the solute that was placed in the solute has completely dissolved in the solvent then it means the solute is soluble, but if some of the solutes were not able to completely dissolved in a solvent, then it means that the solute is slight of somewhat soluble. Now if the solute does not get dissolved in a solvent then it is not soluble. Now, to have accurate results and to minimize any error in the solubility test, make sure to give enough time and to stir the glass for the solute to dissolve also to not put too much of the solute into the solvent. In part “a) Iodine Solubility” the sample of Iodine for the test contained small Iodine crystals. Once the water was added to the Iodine fine crystals, the mixture became an orange/brown liquid. After stirring it, it was noticed that the Iodine became slightly soluble in the water. This is true because some of the crystals were able to dissolve in water but there were still some particles of Iodine that were not able to dissolve in the water. This type of change was physical because no reaction happened, only the change of physical state. For part “b) Sugar Solubility” when the water was added into the sugar, the sugar completely dissolved, there were no particles of sugar left after stirring it and this change is physical because there was no chemical reaction only the change in the state of sugar. In part “c) Calcium Carbonate Solubility”

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when water was added to the powder of Calcium Carbonate, it resulted in a cloudy solution, therefore, Calcium Carbonate was insoluble in water, water, and Calcium Carbonate did not thoroughly mixed. This change was physical because there was no reaction between them. The Calcium Carbonate and water were mixed but did not chemically react. In “Part II C Solubility of a Liquid in Water” when water was mixed with vinegar, there was no physical change. The substance in the tube was clear and colorless and it was completely mixed and miscible. However, when water was mixed with oil, a layer of oil formed on top of the water separating the oil from the water as the water being denser than oil, the oil was coming to the top of the tube this was immiscible. The results indicated that both of the changes were physical changes because there was no chemical reaction and there were no new compounds created by this reaction. In “Part II D Melting Point Determination”, the melting point of sucrose, fructose, and glucose was determined before starting the test this was done so that way the results can be compared to one another of those three substances also, the melting point was determined to have an idea of what was the melting point so when it approached the melting point that was expected then the rate of change in the machine was decreased based on the power level. The melting point was then determined as a range from throw the crystals started to melt and when it was completely melted. The recording of a melting point started when the unknown solid was starting to melt, which started to melt at 102℃, and once the unknown solid was completely melted, it was at 106℃. During the process, it was noticed that the crystalline samples turn from solid to liquid. The melting point of the unknown substance was more similar to fracture which had a melting point of 100℃ to 110℃ while sucrose had a melting point of 150℃ and glucose a melting point of 133℃ therefore the unknown substance was fructose.

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PART III. CHEMICAL PROPERTIES AND CHANGES This part of the experiment was as well divided into subparts, and in this “Part III a) Reaction of a Pure Substance” and “Part B Reaction of Solution” in part a of the experiment, copper was heated, and when the copper wire was heated into the blue flame the copper turned from a reddish-brown to black color. This process is known as oxidation because the heated copper reacted with oxygen in the air to change it chemically, therefore, this process is a chemical process because a new substance was created by the reaction to form copper oxide. In this reaction, the property that was observed was chemical properties and reactivity. In part B “a) Ionic Compound Reacts with a Strong Acid” of the experiment when HCl was added to Sodium Carbonate, bubbles of a colorless gas were evolved releasing CO2, this was because of the releasing of the bubbles, it is a chemical change. When HCl was added to Sodium Sulfate, there was no effective chemical reaction that took place when these chemicals were mixed, therefore, this was a physical change. Some of the chemical properties that were observed in this part of the experiment were both physical properties and chemical change because Sodium Carbonate contained the property of chemical reactivity that when it reacted with HCl it released CO2 and this was a chemical property. Now, when HCl was added to Sodium Sulfate, there was no reaction, and the liquid in the tube was colorless and the HCl was dissolved meaning that it was a physical property. In “Part III B. b) Reaction of Iodine Solution with Soluble Starch” when adding the iodine solution to the starch, the substance turned into a bluish color. This chemical reaction indicated a chemical change because the color of the substance change, besides the reaction indicated that it was a chemical property. III. Conclusions

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After experimenting, some chemical and physical changes were observed in this experiment. Physical changes were observed where the formation of an immiscible mixture, the solubility, and the change of state, while chemical changes that were observed were the changes of color when a reaction happened. The substance in the experiment that was solidified my understanding of physical and chemical properties and the changes of the matter were the Iodine. The processes with Iodine that were performed were sublimation and deposition. When the solubility and the melting point were conducted, this indicated that both were physical properties because it is a characteristic that can be observed without changing the composition of its substance, therefore, these were considered physical properties. However, to minimize some of the errors that could occur in the lab, some skills and lab techniques had to be followed by the book because when observing the physical properties the understanding of how to carefully used the fume hood was needed as well as the Bunsen burners, this was to avoid mistakes that could happen while experimenting. In this experiment, there were some indicators of a chemical change in the reaction with Iodine and starch and the main indicators for these two substances were the change of color of each of the substances. And to minimize errors in observing chemical properties, some lab techniques and some skills were needed. The techniques were followed by the book. For instance, when using the Bunsen burner it was carefully handled as well as the harmful substances, this followed by placing some of the substances that could be dangerous away to not get in contact with those substances. When experimenting, it is important to give detailed observation with gathering qualitative data because that can be collected and recorded to understand why it happens and how. And some reasons this needs to be detailed collected is because it is non-numerical and that is why it is important to give a clear picture of how it happened and the observations that were made that way when someone else tries to do a

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similar experiment, they have an idea of what the outcome will be, or how it will look like. In the study of chemistry, it is extremely important the distinction between chemical changes and physical because knowing their reactivities and understanding how a substance behaves when mixed with some substances. It can help to avoid danger in the lab and keep the environment safe.

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Post Lab Questions 1. What classification of matter will you learn from this experiment? In this experiment, the classification matter that was learned was a pure substance, or the mixture by its competition, as physical or chemical properties, as well as physical or chemical change. 2.

What is your basis for identifying the different classes of matter? Some of the basic identifying different classes of the matter were by differentiating whether it was a pure substance and a mixture and later differentiating compound into an element or compound in a pure substance and homogeneous and heterogeneous in a mixture.

3. How will you determine whether a solid is soluble or insoluble in water? In this experiment, the way it was determined was by observing how much of the solution was dissolved into the water. If the solution was completely dissolved then it was soluble, now if the solution was not dissolved into the water then it is not soluble. If the solution was somewhat dissolved into the water then it was slightly soluble. 4. How will you determine whether a liquid is soluble or insoluble in water? In this experiment, the liquid was determined to be soluble when mixed with water. It was miscible meaning that there was no difference when the liqu...