2. Chromium+oxygen - chromium(III) oxide
balanced

4Cr + 3O2 —> 2Cr2O3

Explanation:

Information from the question include:

Chromium + oxygen -> chromium(III) oxide

From the word equation given above, the equation can be written as follow:

Cr + O2 —> Cr2O3

The equation can be balance by doing the following:

There are 2 atoms of O on the left side and 3 atoms on the right side. It can be balance by putting 2 in front of Cr2O3 and 3 in front of O2 as shown below:

Cr + 3O2 —> 2Cr2O3

Now, we have 4 atoms of Cr on the right side and 1 atom on the left. It can be balance by putting 4 in front of Cr as shown below:

4Cr + 3O2 —> 2Cr2O3

Now the equation is balanced

because u need two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei to form isotopes.

so since they all have the same shape? i mean maybe because m& m and reeses are both chocolates