What I Know Directions. Read the questions carefully. Write your answers on a separate sheet of paper 1. Which of the following best describes matter? A. It has weight. B. It occupies space. C. It is a form of energy. 2. Which is a non-example of matter? D. It has a definite shape. A. clay B fire C. light D. human heart 3. Which statement is TRUE regarding pure substances? A. Pure substances maybe homogeneous or heterogeneous B. Pure substances have definite boiling and melting point. C. Pure substances are physical combinations of two or more elements. D. Pure substances can be further broken down into simpler substances 4. At sea level, an odorless and colorless Liquid A boils at 100°C and freezes at O'C. What inference can be drawn from this observation? A Liquid A is a metal. C. Liquid A is a nonmetal. B. Liquid A is a mixture, D Liquid A is a pure substance. 5. Which of the following are pure substances? A. Aluminum and brass C. Aluminum and salt B. Aluminum and smoke D. Brass and smoke 6. Sugar is heated in a test tube until it is completely changed into a black mass and droplets of water. The experiment indicates that sugar is A. a compound C. a heterogeneous mixture B. an element D. a solution 7. A student investigates the nature of an unknown substance. He decided to heat a sample of a blue-green powder and eventually it tumed into a colorless gas and a black solid. What could be the nature of the original substance and why? A. Mixture, because it is homogeneous B. Mixture, because the material contains two or more substances. C. Compound, because heating the sample produced two different substances D. Element, because the original sample can be further divided into simple substances. 8. A clear, colorless liquid boils sharply at 90.5°C. It dissolves in alcohol and bums when ignited. Analysis reveals that it has a definite composition: 92% carbon and 8% hydrogen by mass. Which properties support that the liquid is pure substance? A. It is a liquid and bums. B. It is clear and odorless C. It dissolves in alcohol and bums. D. It boils constantly and has a definite composition, 9. Which of the following statements distinguishes pure substances from mixtures? A. can be separated by physical means B. consist of two or more kinds of matter C. have no specific solubility and densities D. have constant boiling temperature and melting temperature 10. Which of the following groups contain only pure substance? A. air, methane, sodium chloride C. carbon dioxide, air, water B. ammonia, vinegar, silicon
D. iron, ethanol, calcium fluoride 4​

Please help me