Download the exam here: Exam 3 draft.pdf Download the equation sheet here: Equation Sheet You have 60 minutes to complete the exam; please time yourself accordingly. Once you finish the exam, up to 15 minutes can be used to scan and submit your work to the corresponding Gradescope Assignment.  The exam will consist of 4 open-ended problems, making a total of 105 pts. A calculator is permitted. You are not allowed to access any resources other than the equation sheet during the test. Show all your work to receive full credit on problems. In some cases, this includes drawing a diagram of the problem.

What is the mass percent of sodium in sodium carbonate (Na2CO3)?

Draw the Lewis dot structure of nitrite ion (NO2–) and select the three statements that are true for nitrite ion.

What coefficient is placed in front of O2 to complete the balancing of the following equation?  CH4(l) + ? O2(g) → CO2(g) + 2 H2O(g)

Consider three samples of sodium compounds:1 mol Na2SO4, 1 mol Na2CO3, and 1 Na2HPO4 All three samples have same number of sodium atoms.

Draw the Lewis dot structure of HCN molecule. Which of the following is true?

Consider a redox reaction: Mg + Cu2+ → Mg2+ + Cu. Which of the following is/are true? Select all that apply.(Hint: OIL RIG)(A) Mg is reduced.(B) Cu2+ is reduced.(C) Mg is oxidized.(D) Mg is oxidized.

You MUST submit your work to get credit for this question. No credit will be given if the work is not shown on scratch paper. Make sure to indicate the problem #.Chloroform (CHCl3) is a chemical compound with many laboratory and industrial applications.Calculate the total number of valence shell electrons in CHCl3 molecule and draw the Lewis dot structure for this molecule in the scratch paper.A) Total # of valence shell electrons (VSE) = ……………………………………… (0.5 point). Type your answer in the text box as A) = ….B) Lewis dot structure = ………………………………………………. (2.5 points). Type B) = “See attached file” in the text box provided.C) Does CHCl3 molecule have any polar bond(s)? Why? (1 point) . Type your brief answer as C) = ……D) Is CHCl3 molecule polar or nonpolar? Why? (Hint: SNAP rule) (1 point) Type your brief answer as D) = ……E) The strongest intermolecular forces that are present between two CHCl3 molecules are called _____________. Choose one.(i) dispersion forces (ii) hydrogen bonding  (iii) dipole–dipole forces         (1 point)Type your brief answer as E) = ……

Consider the following reaction:2 H2(g) + O2(g) → 2 H2O(g)If mol H2 reacts with g O2,Determine the theoretical yield of H2O in grams. Hint: Use the Smaller Amount of Product (SAP) approach._______ g H2O. Do not enter unit. You must show your work (SAP math) on scratch paper to get credit.

Which of the following is true about limiting reagent? Select two correct statements.