Chemistry

Answers to Chapter 5 Study Questions

 

1.  a)  6.5 x 102            b)  5 x 10-4          c)  2.07 x 105           d)  1.0 x 106                e)  5.0 x 104

2.  a)  liters (L) or cm3, graduated cylinder, buret, or volumetric flask

b)  grams (g), balance                                c)  meters (m), ruler or meterstick

3.  a)  4            b)  5                 c)  2                 d)  3                 e)  4

4.  a)  1.24 x 8.2 = 10.                                     b)  6.78 - 3.3 = 3.5

      c)  9.999 + 0.22 =  10.22                           d)  (5.67 x 103) x (2.1 x 10-2) = 1.2 x 102, or 120

5.  a) 

      b)  13%

 

6.    =   5.00 x 107 mg

 

7.    =  0.605 lb

 

8.   =   4.60 x 104 cm  (or convert mi ® ft ® in ® cm)

 

9.    =   1.50 x 106  mL

 

10.    =  40.1 lb/qt

 

11.  a)  Container A is the most precise because it has the most number of digits and taking into account the fact that it is off by 2 mL, it never varies by more than 0.08 mL.  You might also say that Container C is the most precise because its volumes are reproducible, but you don’t know whether the actual differences are more or less than Container A.

      b)  Container B is the most accurate, since it is consistently closest to the actual volume.

      c)  Containers A & C show a systematic error:  Container A is 2 mL too high and Container C is 2 mL too low.

 

12.   =   1.8 x 104 ants