Chemistry Final Review1. Write the formula unit for Barium

hydroxide.ans: Ba(OH)2

2. Write the molecular formula for Trisulfur hexaoxide

ans: S3O6

3. How many moles are in 2.3 g of NaClans: 0.0396 moles

4. How many sig figs are in the answer in #3?ans: 3

5. In the reaction of Na + S2 Na2S, write the molar ratio for

Na/Na2S

ans: 4:2Na/S2

ans: 4:16. Given 5 g of sodium, how many grams of Na2S

will be produced?ans: 8.48 g Na2S

7. How many sif fig are expressed in #6 answer?ans: 3

8. Concern the reaction between, Cu + NaCl

What type of reaction may be represented?ans: single replacement

Does this reaction form a produce?ans: No, Cu is less reactive than Na

Would Cu replace Ag in AgCl2

ans: yes, Ag is less reactive than Cu

9. Given 2Mg + PbCl4 Pb + 2MgCl2

Is this a good reaction?ans: yes, Mg is more reactive than Pb

How many mole of PbCl4 is needed to form 5.5 moles of MgCl2 ?

ans: 11 moles MgCl2

How many grams of Mg is needed to produce 0.25 moles Pb?ans: 12 g Mg

How many grams of MgCl2 is produced from 56.4 g PbCl4?ans: 30.6 g MgCl2

10. How many moles are in 5.6 g of CuCl2?

ans: 0.045 moles CuCl2

11. How many molecules of O2 is needed to burn 356 moles of CH4 ?

ans: 4.29 x 1026 molecules O2

12. Given 5.6 x 1021 molecules of Cu(NO3)2, how many grams would you have?

ans: 1.75 g Cu(NO3)2

13.How moles are in 46 g C2H5OH?

ans: 1 mole C2H5OH

14.Given 12 ml of O2 in 2.5 L of water, which is the solute?

ans: O2, of a lesser amount

15. A alloy is composed of 54% Cu and 46% Fe. Which is the solvent?

ans: Cu, of a greater amount.16.Oil will not mix in water. Oil is said to be:

ans: immiscible in water17.Is CaCO3 soluble in water?

ans: insoluble

18.What is the molarity of 0.45 mole of HCl in 35 ml of water?

ans: 12.9 M HCl19. How many grams of NaOH is needed to

make 250 ml of 2 M NaOH?ans: 20 g NaOH

20.Given 54 g CaCl2 dissolved in 150 ml, what is the molar concentration?

ans: 3.3 M21. Is the [OH-] = 5.6 x 10-9 from a pH = 4.765

ans: no, pH = 5.75

22. What is the [H+] from [OH-] = 2.3 x 10-12

ans: 0.004 M23. Is a solution with [OH-] = 8.3 x 10-2 an acidic

or basic solution?ans: basic, pH = 12.9

24. What is the [H+] with a pH = 4.5ans: [H+] = 3.16 x 10-5

25. What is the pOH when the pH = 8.9ans: 14 – 8.9 = 5.1

26.Is a solution basic or acidic with a hydrogen concentration of 1.2 x 10-10 ?

ans: basic, pH = 9.927. Given a 6M HCl, what is the [H+] ?

ans: HCl is strong, 100% dissociation making the [H+] = 6 M

28. What is the [H+] from pOH = 12.5ans: 0.0316

29. What is the pH of the solution in #28?ans: pH = 1.5

30.Given the weak acid of HA with a Ka = 1.6 x 10-5 :

a. How much of the HA remains at equilibrium?

ans: 0.25 – 0.002 = 0.248b. What is the pH of HA?

ans: pH = -log [H+] = 2.731. With an increase in the temperature, there

will be an ___________ in reaction rate.ans: increase

32. A catalyst will increase reaction rate by:ans: lowering the activation energy

33. A substance that slows reaction rate by interfering with reaction pathways is called

ans: inhibitor34.A reduction in the concentration of a

substance would tend to ___________ reaction rate?

ans: slow or reduce

35. What is the formula unit for Iron (III) oxide?

ans: Fe2O3

36. True or false: a molecular compound is composed of a metal bonded to a non-metal?ans: False, this defines an ionic compound

37.The sharing of electrons tends to form what type of bond?

ans: covalent bond

38.Which of the following are diatomic molecules: nitrogen, helium, argon hydrogen

ans: N2 and H2 others are O2, F2, Cl2, Br2 and I2

39. How many atoms of chlorine are in Carbon tetrachloride?

ans: 440. What is the name of AgF ?

ans: Silver (I) fluoride, MUST include Roman numeral with transisitional metal naming.

41. Name Cr(ClO4)4

ans: Chromium (IV) perchlorate42. With ionic compounds a Roman numeral is

used to identify the number of atoms present. In a molecule _______ is used to identify the number of atoms in a molecule.

ans: prefix43. What is the prefix for 6

ans hexa-44. The prefix penta- means?

ans: 5

45. Name the given compounds:a. HBr

ans: hydrobromic acidb. H2SO3

ans: sulfurous acidc. HClO4

ans: perchloric acidd. HF

ans: hydrofluoric acid

46. Write the formula for the following:a. Calcium hydroxide

ans: Ca(OH)2

b. Hydrosulfuric acidans: H2S

c. Chlorous acidans: HClO2

d. Oxalic acidans: H2C2O4

47. Identify the type of reaction and complete:a. CH4 + O2

ans: combustion, CH4 + 2O2 CO2 + 2H2O

b. NaNO3 + Fe(SO4)2

ans: Double replacement4NaNO3 + Fe(SO4)2 2Na2SO4 + Fe(NO3)4

c. Pb + Ca(OH)2

ans: Single Replacement, but a check of the activity series indicate no reaction.

48. Would N2S5 tend to form ionic or covalent bonds?

ans: Non-metal bonded to non-metal is covalent.

49. The further apart two element are place on the periodic table, the __________ ionic the bond between then will be.

ans; more50. What is the molar mass of potassium

dichromate?ans: K2Cr2O7 has a mass of 294 g/mol

51. Food preservatives and weed killer are examples of:

ans: an inhibitor52. What affect would the increase in surface

area have on reaction rates?ans: results in an increase

53. Energy based on position or composition is:ans: potential energy

54. The change in the amount of energy in a reaction is called:

ans: enthalpy of the reaction

55.What is the average reaction rate if at time 2s the concentration was 0.02 M and at time 12 s the concentration is at 0.01 M

ans: -0.001 mole/L s56. What does the (-) value indicate?

ans: reduction in the [reactants] in time

57. The energy of motion is called:ans: kinetic energy

58. What concept is defined by mole solute/Kg solvent?

ans: molality

59.Colligative properties are boiling point elevation, vapor pressure lowering, osmotic pressure and _______________.

ans: freezing point depression60. A _______ is exhibited by the Tyndall Effect

ans: colloid61. Which dissociation will result in a great

depression of the freezing point of water?NaCl or MgCl2

ans: MgCl2 breaks into 3 particles

62.How much mass of water can absorb 4284 J of heat when the temperature changes from 20 oC to 38.2oC?

ans: 56.3 g63. How many joules of heat is exchanged when

156 g of a substance cools from 85.2oC to 5.6oC. The Cp = 0.554 J/goC

ans: -6879.4 J64. What does the negative value in #63 mean?

ans: energy is loss by the substance to the surrounding.

65.In the synthesis reaction of sodium in the present of molecular oxygen, what is the product?

ans: Na2O

66. Will a precipitate form in the following reaction: Ca(NO3)2 + K2SO3

ans: Yes, CaSO3