1. Oxygen cannot be further subdivided into simpler substances by any physical or chemical means. Therefore, it is _______.   a compound   a mixture   an element   Hint Half-n-half Clue   2. Which of the following is the smallest part of a compound, whose properties are the same as those of the compound?   Molecule   Atom   Element   Mixture   Half-n-half Clue   3. Potassium sulfide solution is a _______ mixture.   homogeneous   heterogeneous   4. Which of the following is a pure substance made up of two or more types of atoms or elements?   Mixture   Element   Compound   Half-n-half Clue   5. H2O and FeS represent _______.   mixtures   compounds   elements   Half-n-half Clue   6. The constituents of a mixture do not retain their original properties.   True   False   7. H2 and Fe represent _______.   mixtures   elements   compounds   Half-n-half Clue