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Consider the reaction: 4HCl(aq) + MnO2(s) → MnCl2(aq) + 2H2O(l) + Cl2(g) A sample of 34.9 g MnO2 (molar mass = 86.94 g/mol) is added to a solution containing 42.7 g HCl (molar mass = 36.46 g/mol). a) How many moles of Cl2 can be obtained from MnO2? b) How many moles of Cl2 can be obtained from HCl? c) How many moles of Cl2 can be obtained in this reaction? d) How many grams of Cl2 (molar mass = 70.91 g/mol) can be obtained in this reaction? e) What is the limiting reactant? f) If the yield of the reaction is 75.1%, what is the actual yield of Cl2? Show all your work for full credit. Use the correct number of significant figures.

If 9.78 g of CuSO4 (molar mass 159.61 g/mol) is dissolved in water to make a 0.350 M solution of CuSO4, what is the volume of the solution in milliliters? Show all your work for full credit. Use the correct number of significant figures.

Use the following enthalpies of formations (∆Hof): C2H5OH(l) H2O(l) CO2(g) ∆Hof -278 kJ/mol -286 kJ/mol -394 kJ/mol to calculate the standard enthalpy of reaction (∆Horxn) for the following reaction: C2H5OH(l) + 3O2(g) → 2CO2(g) + 3H2O(l) ∆Horxn = ?

What is  the final pressure of a gas that is expanded from 0.755 L at 24.0oC and 1.25 atm to 2.00 L at 33.0oC?

A sample of 0.725 mol of SO2 occupies a volume of 1.50 L. What will the volume be if the number of moles of SO2 is increased to 0.975 mol, with no change in temperature or pressure ?

An oxygen sample of 1.62 L is at 0.911 atm and 30.0°C.How many moles of oxygen are in the sample?

If 12.6 g of CuSO4 (molar mass 159.61 g/mol) is dissolved in water to make a 0.350 M solution of CuSO4, what is the volume of the solution in milliliters? Show all your work for full credit. Use the correct number of significant figures.

Perform the following conversions between energy units. a) 721 kJ  =  [i_1] ×10[i_2] J b) 3255 kcal  =  [ii_1] × 10[ii_2] kJ c) 5.50 ×106 J  =  [iii_1] × 10[iii_2] kcal

How many double bonds are present in the Lewis structure of NO2- in which the formal charge of N is zero?

Calculate the enthalpy change for the following reaction: 2CO(g) + 4H2O(l) → 2CH4(g) + 3O2(g) ∆H = ? Given the following reactions and their ∆H values: CH4(g) + 2O2(g) → CO2(g) + 2H2O(l) ∆H = -890.0 kJ 2CO(g) + O2(g) → 2CO2(g) ∆H = -566.0 kJ