1.Define displacement reaction. 2.Predict what will happen when: a)Magnesium is put into Silver...

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Transcript of 1.Define displacement reaction. 2.Predict what will happen when: a)Magnesium is put into Silver...

1. Define displacement reaction.

2. Predict what will happen when:

a) Magnesium is put into Silver Nitrate solution

b) Zinc is put into Magnesium Nitrate solution

3. Write down the symbol equation for the reaction between Calcium metal and Lead Nitrate solution

What’s the difference between an “element” and an “ion”?

When two solutions, Barium Nitrate and Sodium Hydroxide are mixed, the solution turns cloudy/milky – which indicates that precipitate has been formed.

a) Write down the word equation for this reaction

b) Write down the symbol equation for this reaction

Displacement ReactionIt is a type of reaction which an element (or ion) replaces another element (or ion) in a compound.

A + BC → B + ACNotice how ‘B’ has been replaced by ‘A’

Example ONE:Silver Nitrate & Copper

When a piece of copper reacts with silver nitrate solution, the copper replaces the silver, producing copper nitrate and silver.

Word equation:

Symbol equation:

Precipitation Reaction (a.k.a. double exchange reaction) AB + CD → AD + CBBaNO3 + NaOH → Ba(OH)2 + NaNO3

Displacement Reaction(a.k.a. single exchange reaction) A + BC → B + AC

Cu + AgNO3 → Ag + Cu(NO3)2

Example TWO:Copper Sulfate & Magnesium

When a piece of magnesium is dropped into copper sulfate solution, the magnesium replaces the copper, producing magnesium sulfate and copper.

Word equation:

Symbol equation:

Practical: Displacement Reaction between Magnesium and Copper Sulfate

• Method: Drop a piece of magnesium ribbon into about 50 ml of copper sulfate solution in a beaker.

• Result:

• Word Equation:

• Symbol Equation:

Displacement ReactionIt is a type of reaction which an element (or ion) replaces another element (or ion) in a compound.

A + BC → B + ACNotice how ‘B’ has been replaced by ‘A’

Displacement ReactionIt is a type of reaction which an element (or ion) replaces another element (or ion) in a compound.

WHY?

Bob = CopperLara = SulfateNick = Magnesium• Lara ditches Bob because she

finds Nick more attractive. (i.e. Nick ‘replaces’ Bob)

• In chemistry, “Attractive” means “Reactive”.

Reactivity Series of Metals

Can you explain why magnesium replaces copper in copper sulfate solution?

What would happen…?

Zinc + Copper sulfate → ???

Iron + copper sulfate → ???

Silver + copper sulfate → ???

Gold + + copper sulfate → ???

Practical: Displacement Reaction between Zinc / Iron and Copper Sulfate

1. Add some zinc granules to about 50 ml of copper sulfate solution in a test tube.

2. Write down the result, word equation and balanced symbol equation

3. Repeat the whole experiment, using iron fillings instead of zinc granules

Practical: Reactivity SeriesMethod:

1. In five test tubes, put about 5 ml of copper sulfate soultion.

2. Put a piece of copper, zinc, tin, lead and magnesium into the test tubes.

Prediction: Which will react and which will NOT react? Why and why not?

• Write down the result

• Write down the word equations AND the balanced symbol equations for the reactions that did take place.

Practical: Reactivity Series 2Task - create your own reactivity series

Copper Iron Lead Magnesium Zinc

Copper sulfate

Iron sulfate

Lead nitrate

Magnesium sulfate

Zinc sulfate