Name:  ______________________________                                                date:  _____________

 

ch. 2, 3, & 4  test                    100 points                                                        Chemistry

 

 

1.  calculate your answer to the proper number of significant figures.  [10 points]

 

a.  264.762  +  83.8  =  ____________

 

b.  2786.294  -  27.8  =  ____________

 

c.  0.082  *  78.6  =  _______________

 

d.  0.03578  +  0.0020  =  _____________

 

e.  (542.8)2  =  ___________________

 

 

2.  write your answer in scientific notation and the proper number of significant figures. [10 points]

 

a.  695.09 =>  ________________

 

b.  0.0570  =>  _______________

 

c.  (765 * 108)  (5.0 * 1012)  =   _________________

 

d.  35.0 + 7.0  =  _______________

 

e.  half of 564 =  _______________

 

 

for full credit in  problems 3 - 4, show your work, circle your answer, have the proper units in your work / answer, and the proper number of significant figures in your answer.

 

3.  conversion factor problems.  [30 points]

 

a.  175 lbs  =  ___  kg

 

 

b.  975 cm3 / min  =  ___  mL / day

 

c.  255 nL / sec =  ___  mL / week

 

 

4.  density problems.  the density of aluminum is 2.70 g / mL.  [30 points]

 

a.  the volume of a 55 g sample of Al is  __.

 

 

 

b.  a 75 mL sample of Al has a mass of  ___.  

 

 

 

c.  a 15 cm long Al cylinder with a mass of 75 g  has a radius =  ___.   [density of Al  =  2.70 g / mL]

 

 

5.  fill-in the below table  [20 points]

 

symbol

name

Hg

 

Si

 

K

 

Ni

 

O

 

 

sulfur

 

lithium

 

Copper

 

Gold

 

iron

 

 

windoł¢&