1. What is the number of atoms of oxygen in 0.250 mol of hydrated zinc nitrate, Zn (NO3)2 • 6H2O?

A. 3.00

B. 12.0

C. 1.81 × 1024

D. 7.22 × 1024

2. What is the mass, in g, of 0.500 mol of 1,2-dibromoethane, CH2BrCH2Br?

Ar (H) = 1; Ar (C) = 12; Ar (Br) = 80

A. 23.5

B. 47.0

C. 94.0

D. 188

3. The equation for the complete combustion of propene, C3H6 , is shown below.

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

Which mixture, when ignited, will lead to incomplete combustion and the formation of CO (g)?

A. 2 dm3 of propene and 10 dm3 of oxygen

B. 0.5 dm3 of propene and 2.3 dm3 of oxygen

C. 1 dm3 of propene and 4 dm3 of oxygen

D. 3 dm3 of propene and 14 dm3 of oxygen

4. What is the percentage yield when 1.1 g of ethanal, CH3CHO, is obtained from 4.6 g of ethanol,CH3CH2OH? Mr (CH3CH2OH) = 46; Mr (CH3CHO) = 44

CH3CH2OH (l) + [O] → CH3CHO (l) + H2O (l)

A. 1.1×46×100/44×4.6

B. 1.1×100/4.6

C. 4.6×44×100/4.6×1.1

D. 1.1×46/44×4.6

5. Which species has 16 protons and 17 electrons?

A. S

B. S

C. Cl

D. Cl

6. Which ion would be deflected most in a mass spectrometer?

A. 79Br+

B. 79Br2+

C. 81Br+

D. 81Br2+

7. Which element has the greatest first ionization energy?

A. Al

B. Ar

C. Cl

D. Cs

8. Which element produces hydrogen gas at the greatest rate when added to water?

A. Ca

B. Cs

C. Li

D. Rb

9. Which element forms more than one stable positive ion?

A. Ca

B. Cr

C. Zn

D. Ba

10. Which statement best describes the lattice structure of solid sodium chloride?

A. Each sodium ion is surrounded by one chloride ion.

B. Each chloride ion is surrounded by two sodium ions.

C. Each chloride ion is surrounded by four sodium ions.

D. Each sodium ion is surrounded by six chloride ions.




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