For this lab the objective is to see how the properties of individual substances compare with properties of mixed substances. For this lab the research questions is mixture, homogenous mixture, and heterogeneous mixture. A mixture is a combination of 2 or more substances that are mixed together physically but not combined chemically. Also a homogeneous mixture is a uniform in structure or composition throughout the substance. Lastly, a heterogeneous mixture is a consisting of dissimilar parts of elements (not the same). In addition, my hypothesis for this lab is the cornstarch and water will make a liquid-solid substance. The Investigating Mixtures Lab objective is to observe that not all liquids behave the same way when mixed with other liquids. Also, my hypothesis for this lab is the vegetable oil will not mix with the water. Conclusion/Analysis: …show more content…
The first question is, After you stir and mix the substances, could you still see the cornstarch and water? No, because they were mixed together. The second question is, Describe how the new mixture is different from the original substances. The answer for that is it looks like a liquid, feels like a solid, but when you touch it, it drips. Another question is, Was the new mixture made from a physical change or chemical change? How do you know? It is a chemical change because it turned into a new substance. In addition, Was the mixture a homogeneous or heterogeneous mixture? Explain. It was a homogeneous because it is the same structure throughout the substance. Also another question is, Was your hypothesis correct? Explain why or why not. My hypothesis was correct because it changed into a new substance that was a liquid-solid. Last question for this lab is, What changes would you make if you could do this experiment again? I would use flour and cornstarch next
Introduction The purpose of this Lab was to identify the density of the unidentified object and determine what substance the unidentified object given by the teacher was. The density calculated in the experiment will stay the same because the density of the unidentified object will stay constant. The Independent Variable of this experiment was the calculated density and the unidentified object given. The Dependant Variable for this experiment was the density.
We were asked to correctly communicate these findings as we tested each of the substances she had encountered with both water and hexane. In experiment number three, The Relationship Between the Volume of a Gas and the Temperature, we where given a list of materials and asked to come up with our own procedure, which we did using zip lock bags filled with air, and submerged fully in a measured amount of water in order to find the volume, and then the change in volume when the temperature of the water was increased. In the fourth experiment we were asked to find the temperature of heated water, based on the cold and warm water. The experiment also required that each section be preformed several times in order to ensure accuracy, and also asked that the experimental responsibilities be split up between lab partners, each doing a section of the testing. This gave us an opportunity to work together with our fellow lab partners, with no one person doing the bulk of the work.
Endothermic reactions absorb energy while exothermic reactions release it. 2.3 How is matter classified? pure substance - matter composed of only one kind of atom or molecule mixture - a collection or two of more pure substances physically mixed together homogeneous mixture - a mixture containing substances that are uniformly distributed heterogeneous mixture - a mixture containing substances that are not evenly distributed phase - any part of a system that has uniform composition and properties elements - the 109 simplest substances from which more complex materials are
For this lab the knowledge to tell the difference between a chemical and physical changes was needed. To tell this the knowledge of the five signs of a chemical change was needed. These five signs are color change, odor change, production of bubbles/gas, production of heat/light, and the production of precipitate. Also prior to the lab one question was provided that needed to be answered. This question was what chemical must be present for a color change.
Beneath Our feet Experiment 1: We put different types of rocks in to three piles that were called Igneous, Metamorphic and Sedimentary. Igneous comes from a volcano. Metamorphic is heat and pressure and Sedimentary is a mixture of conglomerate, fossils and layers. Experiment 2: We put chalk and 3 spoons of sand into a cup and shook it really hard. Some of the sand turned pink which was the colour of the chalk.
After we put the substance on the burner, we weighed it. Each time after we put it on the burner came with the exact same number: 21.16 grams. After we found the mass of the crucible, cover, and hydrated sample, and the mass of the crucible, cover, and dehydrated sample, we subtracted the two values to get the mass of water evolved: 0.24 grams. Then, we subtracted that value to the mass of the hydrated sample to get the mass of the dehydrated sample: 0.76 grams.
When the substance reacted with the solution it turned from its initial color yellow/brown to its final color lilac/violet. The experiment went by easily flowing nicely, although one or two things went wrong, none had any effect on the experiment. It is very important to know what foods are composed of because, knowing what is inside our food is essential for our health. We need to be aware of what things we are consuming and what we should be consuming for our bodies to function properly.
8) Explain how each experiment type (question 7) differs from the
The objective of the sludge lab was to determine how many different pure substances were in the sludge by using the methods and techniques we have learned throughout the year. We had to pick separation methods so we could separate our sludge and then test characteristic properties on our separated liquids and solids. This experiment made us use our knowledge on characteristic properties to pick the ones we should test to help us identify our pure substances. Characteristic properties are properties that help identify a solid or liquid. Each solid or liquid has a certain density, boiling point, solubility, flammability, so if you know what each one is then you can use that information to help you identify your solid or liquid.
Throughout the experiment, copper was altered a total of 5 times, but after the final chemical reaction, solid, elemental copper returned. Each time the solution changed color, a precipitate formed, or when gas appeared, indicated that a chemical reaction was occurring. For the first reaction, copper was added to nitric acid, forming the aqueous copper (II) nitrate (where the copper went), along with liquid water, and
In this lab we used two processes called Diffusion and Osmosis. Diffusion is the movement of molecules from areas of high concentration to areas of low concentration. Diffusion is a process that requires no energy and involves smaller non-polar molecules. In Figure 1 you can see the molecules spreading throughout the glass from the area of high concentration, so that the areas with low concentration are filled evenly as well. The other process was osmosis.
The wax melted first, followed by the salt, and lastly the sugar. The salt not only burned before the sugar, but developed a brown color throughout most of the substance at a faster pace. In the water solubility test, the salt dissolved in the water, as soon as it was properly mixed and the sugar dissolved in the water as well, but was stirred for a longer period of time until it was completely dissolved. The wax did not dissolve in the water, however bits of the substance broke off from the main piece. With this information, the final results included: wax as a nonpolar covalent compound, since the substance melted first and was not soluble in water; salt as a polar covalent compound, since the substance was soluble in water and the second to melt; and sugar as an ionic compound because the substance melted last and was soluble in
You are given a known solid substance with its melting point which has high solubility in hot water and low solubility in cold water. You are assigned the following task: i. Determine if the substance is pure ii. If impure, find a suitable method for its purification by using the given information about the substance How would you proceed, clearly explain your rationale? i. To find if it is a pure substance we see if there is a change in melting point. ii.
This experiment is an attempt to investigate the amount of water potential across root storage plant species. The root storage plant species that shall be used are the carrot and the potato and the method that shall be used is known as Chardakov’s method. Water potential is the tendency of water to enter or leave a cell. Water moves from an area or region of low water potential to an area of high water potential. It is important to note that the highest water potential is 0(the water potential of pure water) and the other water potential values are in negative numbers .
Just by casting a glance at pizza we can easily recognize its ingredients like cheese, pepperoni, mushrooms, olives and chicken etc. Some of the examples of heterogeneous mixture are Fruit loop cereal Nuts in a bowl Rock in the sand at beach