Which statements correctly describe compounds? check all that apply.
1. compounds can be broken down into simpler substances by chemical means.
2. each compound is composed of one type of molecule.
3. compounds can be broken down into simpler substances by physical means.
4. each compound is composed of one type of atom.
5. each compound is composed of two or more types of atoms.
6. compounds cannot be broken down into simpler substances by chemical means.

In a laboratory determination of the atomic weight of tin, a sample of tin is weighed in a crucible. nitric acid is added, and the reaction proceeds to give a hydrated tin(iv)oxide plus no2and h2o. the hydrated tin(iv)oxide is then heated strongly and reacts as follows: sno2.xh2o(s)sno2(s)+ xh2o(g)the sno2is finally cooled and weighed in the crucible. explain the effect on the calculated atomic weight of tin that would result from each of the following experimental errors: (a)considerable spattering occurs when the nitric acid is added to the tin.(b)the hydrated tin(iv)oxide is not heated sufficiently to change it completely to tin oxide.