Which activity most likely involves the direct use of saturated hydrocarbons?
a. burning natural gas
b. dissolving salt in water
c. carving stone with hammer and chisel
d. bending steel by hand

The correct answer is option (a).

Explanation:

Saturated hydrocarbons: These are the hydrocarbons in which only single bond between the carbon-carbon atom is present.On burning they produces carbon-dioxide gas , water and heat. Also during burning they doesn't produces black soots.

Natural gas is mixture of hydrocarbons.These are the saturated hydrocarbons like: methane, ethane, propane and butane.

Where as salt in a water is an aqueous solution of sodium and chloride ions.

Carving stone with hammer and chisel doesn't involve use of hydrocarbons. And the same reason goes for the bending steel by hands too.

Hence, the correct answer is option(a).

chemistry sucks a**

explanation:

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.