C125 midterm - Study guides, Class notes & Summaries

C125 MIDTERM QUIZ QUESTIONS AND ANSWERS Predict products of the following reaction: Cl2 + KI --> - Answer- KCl + I2 What is the reducing agent in the following reaction? Cu(s) + 2 AgNO3(aq) --> Cu(NO3)2(aq) + Ag(s) - Answer- Cu When a colorless Ba(NO3)2 solution mixes with a colorless Na2SO4 solution: - Answer- a precipitate will form A test tube has a colorless aqueous layer of NaI solution and an colorless organic layer of methylene chloride. When a few mL of colorless ...

C125 MIDTERM REVISION EXAM QUESTIONS WITH CORRECT ANSWERS A student experimentally determined the mass % compisition of Ca in CaCO3 to be 38.9%. What is the real mass % composition of CaCO3? What is the % error? - Answer- real = 40.04% error = 2.858% Recall the procedure (chemical measurements). How would the following source of errors affect calculated density of water? A balance was improperly calibrated and always weigh masses 1.0g less than the real masses - Answer- no effect (take...

C125 MIDTERM EXAM QUESTIONS AND ASWERS If 11.3 g of NaCl is dissolved in 100. g of water, what is the percent by mass (mass%) concentration of NaCl in the solution? Note: 1. Use three sig figs for your final answer. 2. Do not enter your answer as fractions. For example, if you think 30% is the correct answer, enter either "30" or "30%". Do NOT enter "0.30". - Answer- 10.2 How many moles of NaOH will be needed to neutralize 0.86 mol of H2SO4? The following equation is NON-bal...

Rearrange the following equation to solve for P. (P+a)(V-b)=nRT - Answer- P=(nRT/V-b) -a What is the slope if B is plotted on y-axis and A is plotted on x-axis? 5A + 3B = 8 - Answer- -5/3 In an experiemnt, the best-fit-line equation between Absorbance (A, unitless) and concentration (c, mg/mL) is used to calculate the concentration of Fe. Based on the best-fit line equation given below, what is the concentration of Fe if the absorbance is 1.25? A = 851 c + 0.03 - Answer- 0.0014 ...

CHEM C125 MIDTERM EXAM QUESTIONS WITH CORRECT ANSWERS

rearrange the ideal gas equation, PV=nRT to the form y=mx+b for the case where V is plotted on the y-axis and n on the x-axis. Name the equation, slope,a dn intercept - Answer- V= RT/P (n) slope: RT/P intercept: none Interpolation - Answer- estimating a value within the range of measured data extrapolation - Answer- projection; conjecture; V. extrapolate: infer (unknown information) from known information best fit line equation commonly takes y=mx+b format. What are your y, x, and...

What is the slope if A is plotted on y-axis and B is plotted on x-axis? 5A + 3B = 8 - Answer- -3/5 Masses (in g) and volumes (in mL) of different amount of an unknown liquid were plotted in Excel and a best-fit-line equation was obtained. What is the unit of the slope for the best-fit-line equation? - Answer- g/mL R square value - Answer- quantity that describes how good experimental data fits into a straight line How many significant figures should the result of the following calcul...

Rearrange the Following equation to solve for C: A = - B/C + D - Answer- C = B / D - A What is the y-intercept if B is plotted on y-axis and A is plotted on x-axis? 5(A + 12) + 3B = 0 - Answer- -20 In y=kx + b, x is - Answer- independent variable Masses (in g) and volumes (in mL) of different amounts of unknown liquid were plotted in Excel. What is the physical meaning of the slope of the obtained best-fit-line equation? - Answer- Density Which one is not rounded correctly whe...

Rearrange the following equation to solve for P. (P+a)(V-b)=nRT - Answer- P=(nRT/V-b) -a What is the slope if B is plotted on y-axis and A is plotted on x-axis? 5A + 3B = 8 - Answer- -5/3 In an experiemnt, the best-fit-line equation between Absorbance (A, unitless) and concentration (c, mg/mL) is used to calculate the concentration of Fe. Based on the best-fit line equation given below, what is the concentration of Fe if the absorbance is 1.25? A = 851 c + 0.03 - Answer- 0.0014 ...