This assignment will be done in groups of two. You can choose whoever you wish in your class to be your partner. You will submit one assignment per group. The scores assigned on the assignment once it is marked will be allocated to individuals in the group. Please ensure that you both participate equally. The assignment is due on the 5th of February 2021. Q1 Q2 Q3 The oxidation of iodide ion by peroxydisulfate ion is described by the equation, 3I- (aq) + S2O82- (aq) → I3- (aq) + 2SO42- If ⁄ = 1.5 and formation of and -3 mol. dm-3 s-1, what is the rate of consumption of I- ? [6] The equilibrium concentrations in a gas mixture at a particular temperature are 0.13 mol. dm-3 H2, 0.70 mol. dm-3 I2, and 2.1 mol. dm-3 HI. What equilibrium concentrations are obtained at the same temperature when 0.20 mol of HI is injected into an empty container? [12] A 1.268 g sample of a metal carbonate MCO3 was treated with 100.00 cm3 of 0.1083 mol. dm-3 H2SO4, yielding CO2 gas and an aqueous solution of the metal sulphate. The solution was boiled remove all the dissolved CO2 and was the titrated with 0.1241 mol. dm-3 NaOH. A 71.02 cm3 volume of NaOH was required to neutralize the excess H2SO4. Q3.1 What is the identity of the metal M? Q3.2 How many litres of were produced if the density of CO2 is 1.799 g cm-3? Q4 [12] [5] Formic acid is an organic acid secreted by ants and stinging nettles. Calculate the pH and concentrations of all species present in a 0.200 mol. dm-3 HCO2H with the Ka = 1.8 10-4. [12] Q5 A 7.0 wt% solution of H3PO4 in water has a density of 1.0353 g cm-3. Calculate the pH and concentrations of H2PO4-, H3O+ and OH- in the solution, Ka = 7.5 10-3.

Show transcript transcripts online experiment: atomic structure [the history of atomic theory] this animation will you test rutherford’s hypothesis that it took a great number of shots to actually hit the nucleus because the size of the atom was so much larger than the nucleus.[clipboard and pencil with a diagram of rutherford’s gold foil experiment] we are going to use a cardboard box to represent the atom, a wooden block to represent the nucleus, and marbles to represent the alpha particles. [animated cardboard box, wooden block, and marbles] the box’s measurements are: length = 50 cm, width = 25 cm, and height = 25 cm. the measurements of the block are: length = 10 cm, width = 10 cm, and height is 5 cm. jose and priscilla will conduct the experiment. [animated boy and girl] priscilla put the block in the box on the floor. jose will close his eyes and drop marbles into the box trying to hit the block. priscilla will count the number of times the marbles hit the block and move the block in the box after each hit. [animated block moving inside the box. marble dropping into the box.] here is priscilla’s data of how many times the marble hit the block. out of 100 marble drops or shots, the marble hit the block 32 times. [data table: first column: marble, with rows 1 to 100; column 2: hit, with rows indicating yes or no. last row: total hits] now you can follow the directions in the experiment to present your findings. present your findings when you are finished with the experiment, complete the following data analysis and record your answers in the essay box below. determine the volume of the box and the block. determine the ratio of the block to the box: multiply this number by 100 to turn it into a percent. complete this statement: the volume of the block is percent of the volume of the box. determine the ratio of the number of hits to the number of shots: multiply this number by 100 to turn it into a percent. complete this statement: the block was hit percent of the time. compare the results of step 2 to the results of step 3. are the percentages similar? write a conclusion discussing the following items: based on your findings, do you think rutherford's hypothesis was reasonable? restate rutherford's hypothesis and describe how you tested it. state whether your results support the hypothesis. if they do not, can you suggest some error in experimental procedure (other than general human error) that might explain it? finally, explain how this experiment confirms the nuclear model of the atom and the idea that most of the atom is empty space.