Ch. 5 & 11 measurement & light                     test                   100 points                                chemistry

For problems involving calculations, show (i) equation or formula to solve the problem, (ii) units in your work and answer, and (iii) the proper number of significant figures in your answer.

1. Write the following numbers in scientific notation and maintain the same number of significant figures; if it’s already in scientific notation, then write “in scientific notation”.  [10 points]

a. 12000  =  _______________________

b.  0.000350  =  _____________________

c. 382.3 * 10 4 =  ____________________

d. 382.3 * 10 - 4 =  __________________

e. 0.00230 * 10 - 4 = ___________________

2. Fill-in the blank; what is the number of significant figures in the following numbers ?  [5 points]

a. 12000.  =  _______________________

b.  0.000350  =  _____________________

c. 382.3 * 10 4 =  ____________________

d. 382.3 * 10 - 4 =  __________________

e. 0.00230 * 10 - 4 = ___________________

3. Fill-in the blank.  [10 points]

a.  2.00  ÷  3.0  =  __________

b. 22.00000  ÷  7.000 = ___________

c. 5.2169  +  125.56  =  ___________

d. eqn1_light  _______________

e. 2.13  =  ________________

4. Solve. [30 points]

a. 275 cm  =  __ m

b. 275 cm2  =  __ m2

c. 37 ºC  =  __ K

d.  325 K  =  __ ºC

e. 1600. meters  =  __ miles; hint:  1 mile exactly = 1760 yards exactly

f.  eqn2_light

5. Solve  [10 points]

a. If light has a wavelength of 275 nm, then what is it’s frequency ?

b. If light has a frequency of 385 MHz, then what is it’s energy ?

6.  In regards to different types of light,  . . .   [10 points]

a. Circle the type of light with the highest energy:  yellow, green, ultraviolet, infrared ?

b. Circle the type of light with the highest wavelength:  yellow, green, ultraviolet, infrared ?

c. Circle the type of light with the highest frequency:  orange, blue, yellow, green ?

d. Referring to an atom’s electron energy level, what is the absorption of light ?

e. Referring to an atom’s electron energy level, what is the emission of light ?

7.  A 35.0 gram sample of an object put into a graduated cylinder containing 75.0 mL of water increases its volume to 87.4 mL.  What is the density of the object ?  [10 points]

8.  If an object has a density of 37 g / mL, then what is . . .   [10 points]

a. 45 g  =  __ mL

b. 15 mL =  __  g

9.  Fill-in the blank; express it as a power of ten; metric prefix.  [5 points]

a. 1 km =  _______ m

b. 1 μs  = ______ s

c. 1 Mg =  ______ g

d. 1 m =  _____ cm

e. 1 L  =  ______  mL