41. Which pair of compounds could combine to produce an ester? I. CH3- CH2 - CH2 - CH3

II. CH3- CH2 - CH2-CH2-OH

III. CH3- CH2 - CH2-COOH

IV. CH3- CH2- CH2- COH

a. I and II
b. II and III
c. II and IV
d. III and IV

b. ii and iii

Explanation:

The ester, Butyl Butanoate is formed when Butanol reacts with Butanoic acid

as seen below;

CH3-CH2-CH2-CH2-OH  +  CH3-CH2-CH2-COOH     >

Butanol                                     Butanoic acid

CH3-CH2-CH2-COOCH2-CH2-CH2-CH3   +          H2O

Butyl Butanoate                                                      Water

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

hope this : )