Answer:
Investigation B, Step 2
Explanation:
The <em>colour change</em> is a good indication of a <em>chemical change</em>. The sugar molecules were most likely changing into something else.
Investigation A, Step 1. <em>Wron</em>g. The dissolving of salt is a <em>physica</em>l process.
Investigation A, Step 2. <em>Wrong</em>. You simply boiled off the water (a <em>physical</em> process) and recovered the salt.
Investigation B, Step 1. <em>Wrong</em>. The dissolving of sugar is a <em>physical</em> process.
Answer:
<em><u>spontaneous composition</u></em> is the ingnition
of the substance due to the repid oxidation of its on material.
There is no requirement of heat of external sources.
<em><u>Rapid composition</u></em> on the other hand release large amount of heat and light energy.
Explosion and the firecracker is the best example of Rapid composition.
Yes, very informational. thank you.