Examen De Practica Quimica

Chemistry 132 Exam 1 September 6, 2012

Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.

____ 1. Which one of the following is a homogeneous mixture?
a.|baked beans|
b.|sugar dissolved in water|
c.|chocolate chip ice cream|
d.|chicken noodle soup|
e.|a jar of chunky peanut butter|


____ 2. Which of thefollowing is a heterogeneous mixture?
a.|mortar (a mixture of calcium carbonate and sand)|
b.|gasoline|
c.|antifreeze (a mixture of water and ethylene glycol)|
d.|sodium chloride dissolved in water|
e.|the air trapped inside a balloon (not including the balloon)|


____ 3. A pure substance composed of two or more different elements is
a.|a homogeneous mixture.|
b.|a heterogeneous mixture.|c.|a polyelement.|
d.|an atom.|
e.|a chemical compound.|


____ 4. A(n) ____ is a pure substance that is composed of only one type of atom.
a.|element|
b.|homogeneous mixture|
c.|heterogeneous mixture|
d.|macroscopic particle|
e.|particulate|


____ 5. What is the correct symbol for phosphorus?
a.|Pm|
b.|P|
c.|Po|
d.|Pt|
e.|Pd|


____ 6. What is the name of the element with thesymbol Ca?
a.|cobalt|
b.|carbon|
c.|calcium|
d.|cadmium|
e.|Californium|


____ 7. The molecular model below depicts a molecule composed of carbon (black), oxygen (gray), and hydrogen (white) atoms. What is the correct molecular formula?



a.|CHO|
b.|C6H6O2|
c.|C6H7O|
d.|C7H6O|
e.|C7H6O2|


____ 8. The density of acetic acid is 1.05 g/mL. What is the volume of 327 g of aceticacid?
a.|2.91 ´ 10-3 mL|
b.|3.21 ´ 10-3 mL|
c.|2.62 ´ 102 mL|
d.|3.11 ´ 102 mL|
e.|3.43 ´ 102 mL|


____ 9. When 24 copper pennies are submerged in water, the pennies displace 8.26 cm3 of water. If the combined mass of the pennies is 73.86 g, what is the density of copper?
a.|0.112 g/cm3|
b.|1.34 g/cm3|
c.|8.94 g/cm3|
d.|32.8 g/cm3|
e.|107 g/cm3|


____ 10. A cube of iron has a massof 29.31 g. If each side of the cube has dimensions of 1.55 cm, what is the density of iron?
a.|0.127 g/cm3|
b.|5.92 g/cm3|
c.|7.87 g/cm3|
d.|12.2 g/cm3|
e.|18.9 g/cm3|


____ 11. Which is a correct method for converting Fahrenheit to Celsius?
a.||
b.||
c.||
d.||
e.||


____ 12. What is a correct method for converting Celsius to Kelvin?
a.||
b.||
c.||
d.||
e.||


____ 13.The wavelength of light emitted from a green laser pointer is 5.32 ´ 102 nm. What is the wavelength in meters?
a.|5.32 ´ 10-9 m|
b.|5.32 ´ 10-7 m|
c.|5.32 ´ 10-5 m|
d.|5.32 ´ 10-3 m|
e.|5.32 ´ 10-1 m|


____ 14. Which of the following postulates of Dalton's atomic theory are now known to be incorrect?

1.|Matter is made up of atoms.|
2.|All atoms of a given element are identical.|3.|Atoms are indivisible and indestructible.|

a.|1 only|
b.|2 only|
c.|3 only|
d.|2 and 3|
e.|1, 2, and 3|


____ 15. From the results of his gold foil experiment, Ernest Rutherford concluded that
a.|electrons have a charge of -1.602 ´ 10-19 C.|
b.|atoms contain equal numbers of protons and electrons.|
c.|uranium ores emit a form of radiation that affect photographic plates.|
d.|alphaparticles are helium nuclei.|
e.|atoms are composed of a small, dense nucleus surrounded by a cloud of electrons.|


____ 16. An atomic mass unit (u) is defined as
a.|the mass of one hydrogen-1 atom.|
b.|1/8 the mass of one oxygen-16 atom.|
c.|1/12 the mass of one carbon-12 atom.|
d.|1.99 ´ 10-23 g.|
e.|the sum of the masses of one proton, one neutron, and one electron.|


____ 17. Whatis the atomic symbol for an element with 28 protons and 31 neutrons?
a.||
b.||
c.||
d.||
e.||


____ 18. What is the identity of ?
a.|Hf|
b.|Zr|
c.|Rf|
d.|Ge|
e.|Cu|


____ 19. How many neutrons are in cobalt-59?
a.|18|
b.|27|
c.|28|
d.|32|
e.|59|


____ 20. All of the following statements are true EXCEPT
a.|for any neutral element, the number of protons and electrons...