1. Which of the Following Is a Physical Property?

1. Which of the following is a physical property?

A. corrosion of aluminum metal B. melting of ice

C. burning a match D. an acid and base reacting

2. Which of the following solutions is the most acidic?

A. 0.5 M NH3 B. 0.3 M HNO3

C. 0.4 M HI D. 0.7 M CH3OH

3. How many grams are in 1.45 L of a substance if the density is 0.564 g/mL?

1.45 L x1000 mL/L = 1450 mL

D=m/V

0.564 g/mL = ‘x’ g/ 1450 mL

‘x’ = 818 g (sig figs)

4. You are given a bottle that contains 4.59 cm3 of a metallic solid. The total mass of the bottle and solid is 35.66 g. The empty bottle weighs 14.23 g. What is the density of the solid?

35.66 g – 14.23 g = 21.43 g metallic solid

21.43 g / 4.59 mL (cm3) = 4.67 g/mL

5. _Polymers__ are made up of many smaller parts called monomers. The element _C_ forms the backbone of nearly all of these.

6. What is the correct atomic symbol for potassium-40?

A. 19K B. 19K

C. 40K D. 40K

7. Complete the following table.

Symbol / 56Fe3+ / 192Os2+ / 197Au3+
Protons / 26 / 76 / 79
Neutrons / 30 / 116 / 118
Electrons / 23 / 74 / 76
Net charge / 3+ / 2+ / 3+

8. The element Mg has three naturally occurring isotopes. The isotopic masses (amu) and % abundances are listed in the table below. Find the average atomic mass.

Isotope / Abundance / Atomic mass (amu)
24Mg / 78.99 % / 23.98504
25Mg / 10.00 % / 24.98584
26Mg / 11.01 % / 25.98259

9. Which of the following ions (denoted by their charge) have the strongest attraction?

A. +1, +2, r=2 B. -2, +3, r=3

C. -1, -1, r=1 D. -2, +2, r=1

10.

Compound Name / Compound Formula / ionic or molecular?
lithium nitrate / LiNO3 / ionic
phosphorous pentafluoride / PF5 / molecular
silicon tetrachloride / SiCl4 / molecular
mercury (II) bromide / HgBr2 / ionic
aluminum hydroxide / Al(OH)3 / ionic

11. Write the correct molecular formula for this compound.

12. Which of the following is not a type of chemical bond?

A. molecular B. ionic

C. metallic D. covalent

Bad question! B,C, and D are the main names we talked about,though.

13. Which of the following is a halogen?

A. bromine B. sodium

C. potassium D. oxygen

14. Complete and balance the following reaction.

2C3H6(g) + 9O2(g) 6CO2 + 6H2O

15. How many atoms ofN are present in 3.1 mg N2O?

3.1 mg x 1 g/1000 mg x 1 mol N2O/44.0128 g x

2 mol N/1 mol N2O x 6.022x1023/mol =

8.5 x 1019 atoms N

16. How many grams of solute are present in 37.2 mL of 0.471 M HBr?

0.471 M = x mol/ .0372 L

‘x’ = .0175 mol HBr x 80.9 g/mol = 1.417 g HBr

17. What ion would you have to add to increase the acidity (decrease the pH) of a solution? H+

18. Complete the following equation, then write the complete and net ionic equations. Are there any spectators? Is there a precipitant?

Ba(NO3)2 + Na2SO4 BaSO4(s) + 2 NaNO3(aq)

net ionic: Ba2+(aq) + SO42-(aq) BaSO4(s)

spectators are Na+ and NO3-. Precipitant is the solid.

19. How many grams of aluminum sulfate are produced when 2.64g of aluminum hydroxide is reacted with excess sulfuric acid?

2Al(OH)3(s) + 3H2SO4(aq) Al2(SO4)3(aq) + 6H2O(l)

2.64 g Al(OH)3 x 1 mol x 1 mol Al2(SO4)3 x 342.14 g = 5.79 g Al2(SO4)3

78.01 g 2 mol Al(OH)3 1 mol

20. A compound consists of 75.69% C, 8.80% H, and 15.51% O by mass. Determine the empirical formula as well as the molecular formula if the molar mass is determined to be 412 g/mol. . *Assume 100 g

75.69g C x 1 mol/12.01 g = 6.30 mol C

8.80g H x 1 mol/1.01 g = 8.71 mol H

15.51g O x 1 mol/16.00 g = 0.97 mol O

*divide all by 0.97 to equal 6.5 mol C, 9 mol H, 1 mol O, times by 2

Emp. formula = C13H18O2

Mol. formula= C26H36O4