5. (5pnts) Which neutral element is isoelectronic with the chloride ion? 6·Spnts

Question

5. (5pnts) Which neutral element is isoelectronic with the chloride ion? 6·Spnts) Arrange the following elements in order of increasing ionization energy, potassium, cesium, bromine, gallium, and neon. Please use the chemical symbols of each element in your answer. 7· (5pnts) In class, we talked a lot about theobromine, C7H8NO2, a compound found in chocolate. If 1.0 oz of milk chocolate contains 60. mg of theobromine, how many theobromine molecules are in one Hershey's kiss, which weighs 0.2 oz? 8. (5pnts) A 0.822-g sample of a compound containing carbon, hvdrogen, and oxvgen was combusted and produced 2.01 g of carbon dioxide and 0.827 g of water. What is the empirical formula of the compound? 9. (5pnts) Consider the following chemical process that is used to convert ammonia into nitrogen monoxide: NH3(g) + O2(g) NO(g) + H2O(g) a. Please balance the chemical equation. b. If 2.00 g of NH3 reacts with 2.50 g of O2, what is the limiting reactant? c. How many grams of NO and H2O form? d. How many grams of the excess reactant remain after the limiting reactant is completely consumed? e. Show that your calculations in parts c and d are consistent with the law of conservation of mass.

Explanation / Answer

   4NH3 + 5O2 ------> 4NO + 6H2O

no of moles of NH3   = W/G.M.Wt

                                 = 2/17 = 0.117 moles

no of moles of O2 = W/G.M.Wt

                              = 2.5/32 =0.078moles

b.5 moles of O2 react with 4 moles of NH3

0.078 moles of O2 react with = 4*0.078/5 = 0.0624 moles of NH3

      O2 is limiting reagent

    NH3 is excess reagent

c. 5 moles of O2 react with NH3 to gives 4 moles of NO

    0.078 moles of O2 react with NH3 to gives = 4*0.078/5 = 0.0624moles of NO

mass of NO = no of moles * gram molar mass

                     = 0.0624*30 = 1.872 g of NO

5 moles of O2 react with NH3 to gives 6 moles of H2O

0.078moles of O2 react with NH3to gives = 6*0.078/5 = 0.0936 moles of H2O

mass of H2O = no of moles* gram molar mass

                     = 0.0936*18 = 1.6848g of H2O

d. no of moles of remaining excess reagent = 0.117-0.0624 = 0.0546 moles of NH3

   mass of NH3 = no of moles of NH3* gram molar mass

                        = 0.0546*17 = 0.923g

Related Questions

Navigate

• Browse (All)
• Browse 5
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.