chemistry lab 4

Read the descriptions below of two substances and an experiment on each. Decide whether the result of the experiment tells you the substance is a pure substance or a mixture, if you can. • Sample A is 100. g of a coarse grey powder with a faint unpleasant smell. 15. g of the powder is put into a funnel lined with a sheet of thick paper. Distilled water is poured slowly over the powder. All of the powder disappears, and the water under the funnel turns a deep purple. • Sample B is a solid yellow cube with a total mass of 50.0 g. The cube is ground to a fine orange powder and added to a 500 mL beaker full of water. The beaker is stirred vigorously. Some of orange powder settles to the bottom of the beaker, and some rises to the top and floats on the water. When the powder at both the bottom and the top of the beaker is filtered out, dried, and weighed, the total mass is measured to be 50.1 g. pure substance Is sample A made from a pure substance or a mixture? If the description of the…

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The following prompt will be used to answer the first six questions. An experiment was performed to separate the components of a binary mixture composed of sucrose (sugar) and sand. The following data was collected in lab during the experiment. Mass of original binary mixture: 20.100 ± 0.001 g Mass of initial filter paper: 21.206 ± 0.001 g Mass of filter paper and isolated sand: 25.226 ± 0.001 g 9b Given the data and information in the prompt, what is the calculated absolute error on the percent of sugar in the mixture? Enter the absolute error you calculated in the box below. You do not need to include the % symbol with your answer.

Please answer question number 1 correctly with the correct answer. there is a picture of an example of a ''Dimensional analysis Format' below. please write out all work showing the math in dimensional analysis format.    Question 3: Calculate the molar mass of each of the following ionic Compounds:   A. KMnO4 B. Ca3(PO4)2

Scenario In an investigation, lab groups combine two compounds, as shown below. Based on the data collected from all lab groups, you realize that one group’s data was not possible.     Mg (s) + 2HCl (aq) → MgCl2 (aq) + H2 (g)   External Data   Group Number Mass of Mg (g) Mass of HCl (g) Mass of MgCl2 (g) 1 5  15                                     20 2 5 15 17 3 5 15 21 4 5 15                                     20 5 5 15                                    19   Prompt  Make a claim about which group’s data is not possible. Use evidence and scientific reasoning to support your claim. Include a rebuttal in your answer.   Claim (1 sentence): ______________________________________________________________.   Evidence 1 (2-3 sentences):…

In a dry test tube, put enough cane sugar to make a layer about 1⁄4 inch deep. heat the tube in the flame while holding a cool inverted beaker near the mouth of the test tube.   Observations:   What is collected in the beaker? Where did this come from? What are the elements present in this substance? What is left behind in the test tube?  What element is it? What elements therefore are present in combination in sugar?

dentity Kyleigh Burcham's Quiz History x Quiz: Chemistry Unit TES /courses/96004/quizzes/378434/take a Join a Game-Quizi. New Tab Google Docs Question 7 Which pure substance below is composed of more than one element? Hydrogen (H) O Radium (Ra) Carbon Dioxide, CO2 O Copper, Cu Question 8 Which of the following is a heterogeneous mixture? O mayonnaise O ketchup O Kool aid O chocolate chip cookies

A mixture is a combination of pure substances, physically combined. Good examples of a solid mixture would be a salad or a bowl mix. Solutions are mixtures too. A spoon full of sugar dissolved in water is an example of both a mixture and a solution. Because m are physical combinations, they are easily separated. Here is a list of mixtures. Match the best method to separate the parts of each mixture. ITEM BANK: Move to Right Gravel and rocks Sand and gravel Sand and wood shavings Boil the water. Collect the solid. Sugar water Dissolve salt in water. Pour through filter paper and collect the sand. Sand and salt Remove iron filings with magnet. Sand and iron filings drag and drop answer here Use a screen to sift and separate the big pieces from smaller pieces. deg and drop answer here Pick out the bigger particles. anddiop sasenbere Add water and float one type of particle. 55 earch 近

4. Gasoline can be reasonably approximated as C9H20 with a density of 0.718 g/mL. Diesel can be reasonable approximated as C14H30 with a density of 0.763 g/mL. (Both gasoline and diesel are complicated mixtures. These formulas are something like weighted averages of the formulas of the different components, where the weighting is based on various quantifiable behaviors. That is, using these artificial formulas for gasoline and diesel allows one to calculate average properties that match what petroleum engineers might measure.) The enthalpy change from burning one mole of gasoline is -6160 kJ. The enthalpy change from burning one mole of diesel is -7940 kJ. Determine which fuel generates the biggest enthalpy change per gram burned, and which generates the biggest enthalpy change per mL burned.

Item at position 3 In the image below, you will see four laboratory spectra for known elements as well as the sample spectra for two unknown objects. Use the laboratory spectra to identify the chemical composition of both unknown spectra: Spectra A and Spectra B.    For each unknown spectra, write out the chemical composition you determined and support your answer by explaining the evidence from the spectra .

True or false: When forming conclusions from an experiment, the researcher should compare the results to the initial hypothesis. * True False True or false: Atomic theory doesn't need to be taken seriously because "it's just a theory" False O True mixture has 24 grams of salt and 36 grams of sugar. What is the percentage of