ANSWERS to Lesson 1.2.5 Activity Questions 1. Make a list of as many patterns as you can find from the card sort poster that occur horizontally. • • • • • elements get smaller # of spokes goes up by 1 atomic mass goes up reactivity goes down then up start as solids—end as gases. 2. Make a list of as many trends as you can find from the card sort poster that occur vertically. • • • • elements get larger # of spokes = atomic mass goes up Left side: reactivity goes up as you go down • Right side: reactivity goes down as you go down 3. Which trend or pattern does each of the following diagrams describe? Size (as you # of spokes go down, atoms get larger) (as you go across, # of spokes increases) Reactivity 4. Where are the metals located on the periodic table? The nonmetals? Metals: Left of the zig-zag Non-metals: Right of the zig-zag 5. Is copper, Cu, a metal or a nonmetal? Explain your thinking. A metal—it’s on the left side of the zigzag. 6. The elements inserted into the card sort from Mendeleev’s table are called transition elements. Do you expect these elements to be solids, liquids or gases? Explain. Solids—they are sandwiched between other solids. 7. Where are most of the gases located on the periodic table? On the far right side. 8. Is thallium, Tl, a solid, liquid, or gas? Solid. 9. In what areas of the periodic table do you find the most highly reactive elements? Lower left, upper right (besides the last column) 10. How would you expect cesium, Cs, to react with water? Explain your reasoning. Explode on contact with water—the other elements in its group are also highly reactive with water. 11. Find the element with the atomic weight 137.3. If there were a card for this element, what would it probably say in the lower left corner? Reacts violently with water. 12. Place the following in order of most reactive to least reactive. rubidium, Rb neon, Ne calcium, Ca silicon, Si Rb, Ca, Si, Ne 13. Elements combine to form compounds. For each of the compounds listed below, specify whether two metals, a metal and a nonmetal, or two nonmetals were combined. a) NaCl, sodium chloride (table salt) Metal & Non-metal b) HC2H3O2, acetic acid (vinegar Non-metals c) CuSn, copper tin alloy (bronze) Metals