Question

Which clue can be used to identify a chemical reaction as a combustion reaction

Answer 1

I don't really know how to eliminate the other choices. The answer is B. Any time oxygen and a hydrocarbon react there is a fire of some sort.

In Alberta Canada where I live, many homes are heated with natural gas. They all burn the same way. They give a characteristic blue flame which, however, is better seen when you burn alcohol. Methane burning looks like this (chemical equation)

CH4 + 202 ===> CO2 + 2H20

Notice that the hydrocarbon and Oxygen are on the left and they "burn" to produce a flame, Water and Carbon Dioxide.

Answer 2

B

Step-by-step explanation:

A comustion is a type of reaction where oxygen reacts with somthing (called fuel) to produce carbon dioxide and water (and byproducts if its a incomplete combustion).

So, the only option that describes a conbustion is a hydrocarbon reacting with oxygen.