The empirical formula is the simplest formula attainable while maintaining the ratio so it will be CH2.
Explanation:
The empirical formula of a chemical compound is the simplistic positive integer ratio of atoms being in a compound. A simple example of this thought is that the empirical formula of sulfur monoxide, or SO, would simply be SO, as is the empirical formula of disulfur dioxide, S2O2.
It's a physical change because the composition of the salt hasn't change. Only the change in substance/form has occured. To tell if something has undergone physical change is:
• Melting
• Boiling
• Freezing
• Condensing
• Breaking
• Bending
• Dissolving
• Molecules can change motion and proximity
To tell if something changed chemically:
• Molecules rearrange with other molecules to make new substance
• Can be production of flames
• Color change
• Bubbling/fizzing
• Temp. change
• change in composition
Answer:

Explanation:
Hello,
In this case, given the balanced reaction:

We can see a 2:4 mole ration between permanganate ion (118.9 g/mol) and manganese (IV) oxide (86.9 g/mol), that is why the resulting mas of this last one turns out:

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20. Would be the right answer
The relationships between molecules atoms and a grain of sugar is the combination of atoms to molecules and the combination of molecules to a compound.
<u>Explanation:</u>
Atom is the foreground to the existence of matter and matter is just another huge combination of atoms. The presence of neutrons, protons and electrons are the important structures of atoms and these atoms are merged to build a molecule.
The relationships between molecules atoms and a grain of sugar is the combination of atoms to molecules and the combination of molecules to a compound.
Molecules are brought together with positive and negative parts of protons and electrons to form bonds and compounds. And compounds come up with elements which connects all these atoms.