1. On burning charcoal which of the following gases is produced?   Hydrogen   Oxygen   Carbon Dioxide   Nitrous Oxide   Hint Half-n-half Clue   2. Which of the following is necessary for a substance to burn?   Oxygen   Light   Gasoline   Hydrogen   Half-n-half Clue   3. Fish breathe through   Skin   Nose   Lungs   Gills   Half-n-half Clue   4. A hygroscopic substance is one which   Absorbs water   Releases water   Releases air   Absorbs air   Half-n-half Clue   5. Which of the following is NOT a noble gas?   Argon   Krypton   Hydrogen   Helium   Half-n-half Clue   6. Nitrogen constitutes nearly __ % of the atmosphere.   57   42   79   21   Half-n-half Clue   7. Which of the following is not a constituent of the atmosphere?   Aluminum   Nitrogen   Oxygen   Carbon Dioxide   Half-n-half Clue   FREE PREVIEW: Last 10 Questions not a part of the free preview. Get Premium Membership to view all questions.