Single Replacement Reactions Experiment 9 Single Replacement Reactions

Single Replacement Reactions Experiment #9

Single Replacement Reactions • Oxidation reduction or Redox reactions • Electron transfer reactions • A + BX B + AX – Element A loses electrons to element B – A + B+? A+? + B – A A+? + ? electrons – B+? + ? electrons B

Experiment • Add sodium metal to water • What happens? ? • Na + H 2 O • Which is more active Na or H?

Experiment • Add potassium metal to water • What happens? ? • K + H 2 O • Which is more active K or H? • Which do you predict is more active K or Na?

Develop a combined activity series • Na > H • K>H • K > Na • Can you put these all together to get an overall activity series?

More experiments • Cr + Na. Cl NR – Which is more active Na or Cr? • Cr + HCl Cr. Cl 2 + H 2 – Which is more active Cr or H? • Ni + HCl Ni. Cl 2 + H 2 – Which is more active Ni or H? • Cr + KCl NR – Which is more active K or Cr?

In summary • K > Na > H • • Na > Cr Cr > H Ni > H K > Cr • Can you determine an overall activity series? • Is there any element that you can not place? Why?

Today’s experiment • In today’s experiment you are going to investigate the combustion of 2 metals and do 6 experiments to determine an activity series. • The formation of a precipitate or the production of bubbles indicates a reaction. • Determine the relative activities of each pair of metals/hydrogen and use these to determine the activity series – You may need to sand some of the metal pieces to get a good surface for reacting – Only metals reacting with acids will produce a gas. Any other gases produced in this lab are a side reaction.

Due today • Experiment 10 – Double Displacement Reactions • If leaving early – Experiment #9 – single replacement – Worksheet #7 – periodic properties – Worksheet #8 – writing reactions