Answer:
D) He did not multiply the chlorine and oxygen atoms by the coefficient 4.
Explanation:
The coefficient 4 at the beginning of the chemical formula indicates that there are four Ca(ClO3)2 molecules. Think of this as Ca(ClO3)2 × 4. This means that he had to multiply the number of atoms for each element by 4 as well, so he should've ended up with 4 total calcium atoms (which is correct), 8 total chlorine atoms, and and 24 total oxygen atoms. He did not get all these answers because he didn't multiply the chlorine and oxygen atoms by the coefficient 4.
Answer: E. none of these
Explanation: because the f-block element is n-2
Answer:
4Al203 + 9Fe -> 3Fe3O4 + 8Al
Amount of Al on reactant side: 8
Amount of Al on product side: 8
Amount of O on reactant side: 12
Amount of O on product side: 12
Amount of Fe on reactant side: 9
Amount of Fe on product side: 9
The correct answer is option C, that is, it appears that ants live in colonies.
The statement, that is, pizza is the best-tasting food on Earth is false, as it cannot be tested. The statement, that is, I believe that there is life on other planets is not a scientific statement, as it is just a belief. The statement, that is, I think nuclear energy is bad is also not a scientific statement as it is just an opinion.
The statement, that is, it appears that ants live in colonies is a scientific statement as one can observe and test this.