Question

1.Gaseous carbon dioxide has a density of 0.001977 g/mL at standard conditions. What is the mass of 50.00 cm³ of gaseous carbon dioxide?

a.0.09885 g b.9.885 g c.3.954 x 10^-5 g d.2.529 x 10⁴ g e.0.9885 g

2.The half-life of tungsten-187 is 0.9875 days. How much of a 10.0 gram sample remains after 71.1 hours?

a.1.25 g

b.5.00 g

c.2.50 g

d .Not enough information is given.

3 .If 35.0 mL of 0.550 M KOH are needed to neutralize 15.0 mL of an HI solution, what is the molarity of the HI solution?

a.1.28 M b. 0.236 M c. 1.28 x 10^-3 M d. 9.55 M

4. Silver Y moths have migration speeds as high as 65 kilometers per hour. Calculate their speed in mm/s.

a.18000 mm/s b.1400 mm/s c.180 mm/s d.1100000 mm/s

5.  Which compound below contains a polar covalent bond?

a. H₂O b.ZnS c. C₆H₆ d. F₂ e. All of these have polar covalent bonds. f.None of these have polar covalent bonds.

6 How many covalent bonds does Sn form in most of its covalent compounds?

a.Sn does not form covalent compounds. b.2 c.4 d .3

7.An unknown metal (X) forms the compound XO₂. If X forms a compound with chloride ion, what would the formula of that compound be?

XCl₄

XCl₃

XCl₂

XCl

X₂Cl

8

9

8.)Which of the following compounds is platinum (IV) fluoride?

PtF₄

Pt₄F

Pt₄F₄

Pt₄F₂

PtF