Question

1.

Which name–formula pair is incorrect?

A.magnesium sulfate heptahydrate, MgSO₄·7H₂O

B.dinitrogen tetroxide, N₂O₄

C.strontium nitride, Sr₃N₂

D.hypochlorous acid, HClO₂

E.titanium(IV) carbide, TiC

2.

The complete combustion of phenylhydrazine, C₆H₅NHNH₂, with the oxidizer dinitrogen tetraoxide is shown in the following equation:

__ C₆H₅NHNH₂ + __ N₂O₄ → __ CO₂ + __ H₂O + __ N₂

When this equation is balanced, the sum of all the coefficients (using smallest whole numbers) is:

A.25

B.20

C.10

D.15

E.30

3.

Sorbose, C₆H₁₂O₆, is used in making vitamin C. A sorbose sample containing 13.0 g of carbon atoms also contains ____ g of hydrogen atoms.

A.4.36

B.1.56 × 10²

C.2.18

D.1.08

E.13.0

4.

A sample of an oxide of antimony (Sb) contained 20.0 g of antimony combined with 6.6 g of oxygen. What is the simplest formula for the oxide?

A.Sb₂O

B.SbO₂

C.Sb₂O₅

D.Sb₂O₃

E.SbO

Answer 1

1) D   ( actually hypochlorous acid is HClO )

2) B   ( C6H5NHNH2 + 4N2O4 ---> 6CO2 + 4H2O + 5N2 )

3) C    2.18

4) C    Sb2O5