CHEM133 Week 4 Lesson 2 Quiz

1. Question: If 0.274 moles of a substance weighs 62.5 g, what is the molar mass of the substance, in units of 2. Question: What volume of 18 M sulfuric acid must be used to prepare 1.80 L of 0.215 M H2SO4? 3. Question: What is the molecular mass of Br2? 4. Question: What is the molar concentration of sulfate ions in a 0.150 M Na2SO4 solution? 5. Question: How many moles of hydrogen chloride are contained in a 52.6 g sample of this gas? 6. Question: 1.00 mole of O2 contains the same number of molecules as 7. Question: You have a sample of zinc (Zn) and a sample of aluminum (Al). You have an equal number of atoms in each sample. Which of the following statements concerning the masses of the samples is true? 8. Question: A sample of ammonia has a mass of 45.5 g. How many molecules are in this sample? 9. Question: Naturally occurring copper exists in two isotopic forms: 63Cu and 65Cu. The atomic mass of copper is 63.55 amu. What is the approximate natural abundance of 63Cu? 10. Question: What is the mass of 4.50 x 1022 Cu atoms? 11. Question: Based on the solubility rules, which of the following compounds should be insoluble in water? 12. Question: What is the molar mass of Co(NO3)2? 13. Question: According to the following balanced chemical equation, 14. Question: For the reaction 4FeCl2(aq) + 3O2(g) → 2Fe2O3(s) + 4Cl2(g), what volume of a 0.890 M solution of FeCl2 is required to react completely with 8.71 × 1021 molecules of O2? 15. Question: Which of the following will occur when solutions of CuSO4(aq) and BaCl2(aq) are mixed? 16. Question: How many grams of calcium chloride are needed to produce 1.50 g of potassium chloride? 17. Question: What is the oxidation number change for the iron atom in the following reaction? 18. Question: What is the sum of the coefficients when the following equation is balanced using the lowest whole-numbered coefficients? 19. Question: Using the redox reaction below determine which element is oxidized and which is reduced. 20. Question: What are the coefficients in front of NO3 -(aq) and Zn(s) when the following equation is balanced in a basic solution? 21. Question: If the percent yield for the following reaction is 65.0%, how many grams of KClO3 are needed to produce 32.0 g of O2? 22. Question: A 50.0 mL sample of 0.436 M NH4NO3 is diluted with water to a total volume of 250.0 mL. What is the ammonium nitrate concentration in the resulting solution? 23. Question: If the percent yield for the following reaction is 75.0%, and 45.0 g of NO2 are consumed in the reaction, how many grams of nitric acid, HNO3(aq) are produced? 24. Question: Which substance is the limiting reactant when 2.0 g of sulfur reacts with 3.0 g of oxygen and 4.0 g of sodium hydroxide according to the following chemical equation: 25. Question: Write a balanced net ionic equation for the reaction of AgNO3 (aq) with KBr (aq).