Why are the last three dilutions plated, as opposed to only one dilution?

Based off information from the attachment, please help with #9 on second attachment

A student pipetted 10 mL of a sample solution into a 250 mL volumetric flask and diluted it to the mark with distilled water. The student then, pipetted 10 mL of this new solution into a 50.00 mL volumetric flask and diluted it to the mark with water. What is the dilution factor of the final solution?   25X   100X   125X   5X   50X

5.00 mL of stock solution is diluted to 25.00 mL, producing solution ALPHA. 10.00 mL of solution ALPHA is diluted to 25.00 mL, resulting in solution BETA. 10.00 mL of solution BETA is then diluted to 25.00 mL, producing solution GAMMA. dilution factor for ALPHA from stock solution = 0.167 dilution factor for BETA from ALPHA solution = 0.0476 part c and d?

Data obtained: Chips # of extractions Chips' weight (g) Fat weight (g) Regular  3 20.043 6.745   3 20.187 6.438   3 20.198 7.451 Low fat  3 19.456 3.982   3 20.072 4.547   3 20.192 4.589   Mass percent is a method of expressing the concentration of a substance in a mixture or element in a compound. It is calculated as the mass of the component divided by the total mass of the mixture and then multiplied by 100 to get the percent. The formula is: mass % of component= (mass of component / total mass) x 100%   1) Reproduce the following table, and use the data to determine the mass % of fat in the chips for each trial. 2) Show one example calculation. Chips Trial % by mass of fat Regular 1     2     3   Lowfat 1     2     3

Epsom salt is a product that may be added to a bath to help ease sore muscles. Epsom salt crystals Epsom salt ground crystals A materials scientist tested two forms of Epsom salt under different conditions to see which would dissolve the fastest. The test information is displayed in this table. Sample Mass Form Water temperature A 50 grams ground crystals 30°C B 100 grams crystals 20°C 50 grams 100 grams ground crystals 20°C crystals 30°C Which sample of Epsom salt would you expect to dissolve the fastest? O A. A В. В ос. С O D. D

2.00 mL OF 5.80 x10-"M AGNO g 245.0 mL of 3.35 X10 M NazS and + Na, Scaas 2 NANO3 tazy 248.19 1549 2709 2 Ag NO3 78.19 Nans Agzs 2 NANO3 inirial Change Final

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Q) A student misreads the directions and adds 4.0 g of benzoic acid instead of 0.4 g. What do you expect to happen? Would the experiment still be valid? Explain your reasoning.     Pure Lauric Acid Lauric Acid + 0.4 g Benzoic Acid Lauric Acid + 0.5 g Benzoic Acid Mass of Lauric Acid   3.03g 3.00g 3.00g Mass of Benzoic Acid   0 g 0.40g 0.50g Freezing Point   43’C 39’C 38’C Freezing Point Depression *   4’C 5’C Molality of Benzoic Acid in Lauric Acid*   1.026 mol/kg 1.282 mol/kg Moles of Benzoic Acid *   0.003 moles 0.004 moles Experimental Molar Mass of Benzoic Acid *   133.3g/mol 125 g/mol Average Molar Mass *   129.15g/mol   Percent Error *   5.75%

An impure sample contains 1.01 g of impurities and 4.92 g of benzoic acid.  The impure sample is dissolved in water, then heated.  The solution is then cooled.  How many grams of benzoic acid will recrystallize when the solution has cooled? Include the unit and two decimal places in your answer. The solubilities of the impurity and benzoic acid in hot water are found as an item in the Recrystallization Experiment folder.   Solubility Data for Report Questions 10  Compound Cold Water solubility Hot Water Solubility Benzoic acid 0.42 g per 100 mL of water 5.79 g per 100 mL of water Impurity 0.61 g per 100 mL of water 4.62 g per 100 mL of water