Burning a magnesium ribbon in the air is an addition reaction while heating potassium manganate 7 is a decomposition reaction.
<h3>Addition and decomposition reactions</h3>
Magnesium burns in air to produce magnesium oxide as follows:

Potassium manganate 7 burns to produce multiple products as follows:

Thus, the MgO will be heavier than Mg. On the other hand,
will be less heavy than
.
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Answer:
testable questions are answer through observation or an experiment that provides evidence that the questions connects to the scientific concepts rather the opinion feelings
therefore the question can be tested through observation or experiment
Answer:
<h3>The answer is 4.41 g/cm³</h3>
Explanation:
The density of a substance can be found by using the formula

From the question we have

We have the final answer as
<h3>4.41 g/cm³</h3>
Hope this helps you
C. pouring honey on a plate so the density of thickness and stickyness would
be the highest