CHEM 1115 Unit 1 Practice Problems

CHEM 1115 Final Review Practice Problems

These problems do not represent everything that will be on the final exam. Use your objectives to study!!!

1. For each of the following elements, list its elemental symbol and classify it as: (see page 9 of syllabus)

 metal, nonmetal, or metalloid  main group element, transition metal, lanthanide or actinide  alkali metal, alkaline earth metal, halogen, noble gas, or none of these

argon aluminum silicon fluorine hydrogen potassium uranium cerium barium gold

Give the name for the following:

Fe O N Cl Na Ca He Pb Hg

2. List the chemical formula for each of the diatomic elements.

3. Write the formula or name for the following ions. (page 12 of syllabus) sodium ion H+ calcium ion Cl- iron (II) ion NO3- lithium ion OH- phosphate ion Fe3+ 4. Give the names for the following compounds.

Na2CO3 Fe2O3 AgNO3 Ca3N2 BaCl2 Al2(SO4)3 FeCl2 Mg(OH)2 Zn(C2H3O2)2

5. Give the correct formula for the following compounds

Silver sulfate Iron (II) phosphate Barium acetate Cesium fluoride

Aluminum carbonate Ammonium sulfide Sodium bicarbonate Sodium cyanide

6. A 25.0 mL sample of liquid has a mass of 26.897 g. What is the density of the liquid?

7. What is the mass of a 6.2 cm3 piece of metal if its density is 8.91 g/cm3?

8. What volume of a liquid with a density of 0.890 g/mL is needed to provide 125.20 g?

9. A silver colored solid cube has the following dimensions: 10.50 cm x 0.50 cm x 1.00 cm.

a. If it has a mass of 13.13 g, calculate its density.

b. If the density of aluminum is 2.702 g/cm3, is this sample pure aluminum?

3 10. Osmium has a density of 22.6 g/cm . What is the mass of a block of osmium that measures 1.01 cm × 0.233 cm × 0.648 cm in grams?

11. Write the electron configuration for the following:

c. O2-

12. Write the electron configuration using core notation for the following:

c. the ion formed by Br

13. Consider each pair separately. Which substance in each pair has the larger radius?

a. Ca vs. Ba

b. Br – vs. Br

c. Li+ vs. Li

d. S2- vs. Ca2+

e. B vs. F

14. Is each of the following sets of quantum numbers an allowed set? If not, why not?

a. n = 4, l = 2, ml = -1 b. n = 3, l = 0, ml = 2

15. Which of the following statements describes some aspect of the QM model of the atom?

a. Electrons have a wave-like properties.

a. If the energy of an electron is known for certain, then its exact location can be found as well.

b. Three quantum numbers are used to describe an orbital.

c. Electrons are found in circular orbits around the nucleus.

d. The azimuthal quantum number describes the energy of an electron.

16. What are the quantum numbers associated with the following subshells:

17. Write the Lewis symbol for the following atoms or ions:

a. P b. S2- c. Na

18. Draw an appropriate Lewis structure for each of the following.

– a. NO2 b. ClF3 c. COCl2 (carbon is central atom) d. BrF5 e. SO2

19. For each of the molecules or ions given in problem 18, give the name of the electron domain geometry, the molecular geometry, and sketch each one.

20. Give the names for the following compounds.

Cl2O7 NO2 CS2 PBr3 SCl2 CO H3PO4 NaClO

21. Give the correct formula for the following compounds:

dinitrogen tetroxide sulfur trioxide diphosporus pentoxide silicon dioxide hydrochloric acid surfuric acid periodic acid nitric acid 22. Balance the following equations:

Na + H2O à NaOH + H2

S8 + O2 à SO3

P4O10 + H2O à H3PO4

C3H8 + O2 à CO2 + H2O

Al2(SO4)3 + Ca(OH)2 à Al(OH)3 + CaSO4

23. Aluminum hydroxide reacts with sulfuric acid to form aluminum sulfate and water.

a. Write a balanced equation for this reaction. b. How many moles of aluminum sulfate with be produced using 0.26 moles of aluminum hydroxide? c. How many moles of sulfuric acid are needed to completely react with 0.50 moles of aluminum hydroxide? d. How many grams of aluminum sulfate can be produced using 10.0 g of aluminum hydroxide? e. How many grams of sulfuric acid are needed to react with 1.25 moles of aluminum hydroxide? f. How many kilograms of aluminum hydroxide are needed to react with 5150 g of sulfuric acid?

24. Complete and balance the following reactions. Include the physical state of each of the products.

a) BaCl2(aq) + Na2SO4(aq) ®

b) AlCl3(aq) + AgNO3(aq) ®

25. Write the complete ionic equation and the net ionic equation for the following:

a) Fe(NO3)3(aq) + 3KOH(aq) ® Fe(OH)3(s) + 3KNO3(aq)

b) 3Fe(C2H3O2)2(aq) + 2Na3PO4(aq) ® Fe3(PO4)2(s) + 6NaC2H3O2 (aq)

26. Complete and balance the following acid-base neutralization reactions. Write the complete ionic equation and the net ionic equation for each reaction.

a) Fe(OH)3(s) + HCl(aq) ®

b) Al(OH)3(s) + H2SO4(aq) ®

27. Write complete ionic and net ionic equations for the following reactions:

Pb(s) + Cu(NO3)2 (aq) ® Pb(NO3)2 (aq) + Cu(s)

Fe(s) + 2HCl(aq) ® FeCl2 + H2(g)

28. What volume of 2.40 M MgCl2 is needed to provide 0.225 mol of chloride ion to a reaction?

29. What mass of Na2SO4 is needed to make 250.0 mL of 0.850 M Na2SO4?

30. Describe in detail how you would prepare 500.0 mL of 1.00 M NaCl from solid NaCl.

31. What volume of 12.0 M HCl is needed to prepare 600.0 mL of 1.75 M HCl?

32. Describe in detail how you would prepare 250.0 mL of 2.0 M HCl from 12.0 M HCl.

33. What is the volume of 0.250 moles of a gas at 75°C and 1.50 atm?

34. A 25.0 g sample of CO2 is placed in an 8.00 L steel tank. What is the pressure in torr in the tank at 45°C?

35. How many moles of a gas are present in 25.0 L steel tank at 1.5 x 102 kPa and 165oC?

36. At what temperature in °C would 25.0 g of NH3 in a 27 L steel tank have a pressure of 1.5 atm?

37. A sample of gas in a 1.00 L cylinder-piston assembly has a pressure of 2.50 x 105 Pa at 115°C. If the gas is cooled to room temperature (25°C) and the gas is compressed to a volume of 550 mL, what is the pressure (in SI units) of the gas.

38. A sample of gas in a 35.0 L cylinder-piston assembly has a pressure of 1.55 atm at 125°C. If the pressure on the gas increases to 3.0 atm while the volume of the gas decreases to 25.0 L, what is the temperature (°C) of the gas?

39. How much heat is gained or lost when 2.5 g of KClO3 decomposes according to the

reaction: 2 KClO3 (s) à 2 KCl (s) + 3 O2 (g) H = -89.4 kJ

40. How much heat is gained of lost when 7.4 g of KClO3 is formed according to the reaction in question 39.

41. The specific heat of iron is 0.108 cal/g-K. How much heat in kJ is needed to bring the temperature of 0.250 moles of iron from room temperature (25oC) to its melting point (1535oC)?

42. What is the specific heat of copper if 1.376 kJ of heat must be added in order to raise the temperature of 55.0 g of copper from 22.5oC to 87.5oC.

43. Use the following phase diagram to answer the following questions:

a. Which point represents a melting point of the substance?

b. Which point represents the critical point?

c. Draw an arrow on the diagram showing the change that occurs during condensation.