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Nitrogen combines with lithium as shown below.  If we want to produce 3.60 mol of lithium nitride, how many moles of lithium would we need to start with? (Nitrogen is in excess.)             6Li(s) + N2(g)  →  2Li3N(s)

If a solution is prepared by diluting 40.0 mL of 0.200 M CsCl to 250.0 mL, what is the new solution’s concentration in molarity?

Each curve on the graph below represents a different gas.  Which one of the gases has the lowest molar mass?

Atoms X, Y, Z, and R have the following nuclear compositions:               Which two are isotopes?

What is the abbreviation for “three times a day”? 

Truth in sentencing requires offenders to:

Which of the following compounds would you expect to be ionic? NH3{“version”:”1.1″,”math”:”NH3″} SCl6{“version”:”1.1″,”math”:”SCl6″} H2O2{“version”:”1.1″,”math”:”H2O2″} MgO{“version”:”1.1″,”math”:”MgO”} K2SO4{“version”:”1.1″,”math”:”K2SO4″} CO{“version”:”1.1″,”math”:”CO”} SO3{“version”:”1.1″,”math”:”SO3″} SrCl2{“version”:”1.1″,”math”:”SrCl2″}

The phosphorus pentoxide used to produce phosphoric acid for cola soft drinks is prepared by burning phosphorus in oxygen. If 0.200 mol of oxygen is reacted with an excess of phosphorous, what is the percent yield of the reaction if 10.0 g is isolated?P4(s) + 5O2(g) → P4O10(s) Write out your calculations and answers clearly, with all numbers labeled correctly, on a piece of paper.  Right after submitting your exam, upload your photos to the Assignment Box, “Calculations for Exam 2 (Chapter 3)”

Kaolinite, a clay mineral with the formula Al4Si4O10(OH)8, is used as a filler in slick-paper for magazines and as a raw material for ceramics. Analysis shows that 14.35 g of kaolinite contains 8.009 g of oxygen. Calculate the mass percent of oxygen in kaolinite. Write out your calculations and answers clearly, with all numbers labeled correctly, on a piece of paper.  Right after submitting your exam, upload your photos to the Assignment Box, “Calculations for Exam 2 (Chapter 3)”

Which of the following should be considered a weak electrolyte?