goldentigers.org #25 Copper Lab Chemistry

goldentigers.org Nov 23(A) & Nov 24(B) Big Idea: Show me the Money! Objective: SWBAT observe a chemical reaction Do Now: Read, annotate, answer questions Agenda ­ Do Now10 min ­ Group Leader/Greeter ­ Homework & Do Now Review05 min ­ CRS Skills & CER Practice20 min ­ Copper Lab35 min Homework: Complete table on worksheet #25

goldentigers.org CRS Clicker Practice Period 2, Group n= Atomic Mass Table 1: Transitions to n=1 TransitionInitial Group Drop in Boiling Point A41820 B31200 C21180 Table 2 StateTemp Solid<1000 Liquid Gas>1500 Figure 1

goldentigers.org 1) In Figure 1 and Table 1, the atomic mass needed to produce a drop in boiling point of 1300 would be closest to: IOD 504 A. 7 B. 9 C. 10 D

goldentigers.org 2) Which model(s) imply that the drop in boiling point depends on the initial group? IOD 601 A. Chemical model B. Physical model C. Both chemical and physical models D. Neither chemical or physical models 30

goldentigers.org 3) From Table 1, what can you predict about the drop in boiling point for a transition from initial group 5 to group 1? IOD 506 A. Boiling point drop would be greater than a n=4 to n=1 transition B. Boiling point drop would be smaller than a n=4 to n=1 transition C. Boiling point drop would be the same as a n=4 to n=1 transition D. No boiling point drop will occur 30

goldentigers.org 4) Per Fig. 1 and Table 1, which statement is NOT accurate? EMI 601 A. The higher the initial group, the higher the boiling point drop B. It takes an atomic mass of about 11 to get a boiling point drop of about 1000 C. For transitions to n=1, the lower the initial group, the lower the boiling point drop D. Atomic mass is related to period number 30

goldentigers.org 5) Based on Table 1 and Table 2, if a substance boiling at 2000 degrees goes through a group n=4 to n=1 transition, what state will it end up in? IOD 502 A. Solid B. Liquid C. Gas D. Plasma 30

goldentigers.org 30 Second Stretch Clear desk of everything except ­ Today’s worksheet ­ Pencil

goldentigers.org Purpose (Write Down) Determine how copper (Cu) changes when it is heated (Think About) Should copper be one of the metals you consider for your coin design?

goldentigers.org Hypothesis We will observe a chemical reaction by heating up some copper powder We are starting with pure Cu (copper) We will end with a different substance Will the mass increase, stay the same, or decrease?

goldentigers.org What’s New Crucible Tongs

goldentigers.org Safety First! What do we do before we start a lab? Put on aprons and goggles! How long do we keep them on? Until after lab cleanup! SPECIAL SAFETY NOTE ­ We will be using hotplates set on high (10) ­ They are HOT! Keep in middle of table! ­ Carefully put them back in drawers ­ Dump back in cup; NOTHING thrown out! ­ If crucible breaks, raise your hand for help

goldentigers.org Procedure (in Groups)  1. Put hotplate in middle of table; turn on, set to 10  2. Measure and record mass of empty crucible  3. Add all of the powdered copper (about 4g of Cu) to the crucible, and record mass again  4. Calculate mass of the Cu  5. Record observation of color and texture of Cu. Record start time. Put crucible on hotplate.  6. With tongs, remove crucible from hot plate every two minutes, record observations, GENTLY break up solid chunks with spatula, then put back on hotplate.  7. Continue for a total of 10 minutes. Turn off hotplate.  8. Measure and record mass of crucible and Cu.  9. Calculate mass of Cu. Dump Cu back in paper cup  10. Put scale and hotplate back in drawers. Put everything else back in bins. Throw nothing out.