Question | Answer |
3.1 In a careful experiment, a chemist burns 15.4 kg of wood in a fireplace. The chemist collects all of the substances produced by the fire. He measures the mass of ash produced to be 925 grams, the mass of carbon dioxide produced to be 15.14 kg... | |
3.1(continued) ...and the mass of water produced to be 3.12 kg. How much oxygen was used up by the wood while it burned? | 3.8 kg |
3.2 Which of the following elements is (are) metal(s)? O, Mg, I, In, Os, Rn, H | Mg, In, and Os. |
3.3 If you want to make a wire for an electrical system and you only have the following elements to work with, which should you choose? Ni, S, Se | Ni |
3.4 Which of the following would you expect to break when it is bent? Rh, Ba, P | P |
3.5 When 12.0 grams of the element (C) react with 4.00 grams of the element (H), natural gas is produced. There is no leftover carbon or hydrogen when these quantities are used. How much carbon and hydrogen would you need to make 100.0 g of natural gas? | 75.0 g carbon. 25.0 g hydrogen. |
3.6 A chemist decomposes 30.0 grams of a purple powder into 13.6 grams of the element cobalt (Co) and an unmeasured amount of chlorine gas. The chemist uses the results of this experiment to help him determine the recipe for making this purple powder... | |
3.6(continued) ...from its elements. He then decides to make 1.00 kg of it. How much cobalt and how much chlorine gas will he need? | 453.3 g cobalt. 546.7 g cholorine |
3.7 Give the formula for each of the following molecules: (a.) A molecule that has 1 atom of sodium and 1 atom of chlorine (b.) A molecule that is made up of 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms | (a.) NaCl (salt) (b.) C₆H₁₂O₆ (glucose) |
3.7(continued) (c.) A molecule with 2 sodium atoms, 1 carbon atom, and 3 oxygen atoms | (c.) Na₂CO₃ |
3.8 How many of each atom exist in the following molecules? (a.) KMnO₄ (b.) Na₃PO₄ (c.) RbCl | (a.) Potassium: 1, Manganese: 1, Oxygen: 4 (b.) Sodium: 3, Phosphorus: 1, Oxygen: 4 (c.) Rubidium: 1, Chlorine: 1 |
3.9 Classify the following compounds as ionic or covalent: (a.) CH₄ (b.) KCl (c.) RbC2H3O₂ (d.) C₂H₄Br₂ | (a.) covalent (b.) ionic (c.) ionic (d.) covalent |
3.10 Name the following compounds: (a.) SF₆ (b.) K₃N (c.) P₂O₃ (d.) CaCl₂ | (a.) Sulfer hexafloride. (b.) Potassium nitride. (c.) Diphosphorus Trioxide. (d.) Calcium hloride. |
3.11 Give the chemical formulas for the following covalent compounds: (a.) oxygen dichloride (b.) dicarbon dihydride | (a.) OCl₂ (b.) C₂H₂ |