Reaction of Alkali Metals with Water Observations Flame floats/surface, melts, bubbles/moves/fizz...

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Reaction Reaction of Alkali of Alkali Metals Metals with Water with Water

Transcript of Reaction of Alkali Metals with Water Observations Flame floats/surface, melts, bubbles/moves/fizz...

Page 1: Reaction of Alkali Metals with Water Observations Flame floats/surface, melts, bubbles/moves/fizz Behaviour NothingPopSplint Blue/baseLitmus SoftestSofterSoftHardness.

Reaction of Reaction of

Alkali Metals Alkali Metals

with Water with Water

Page 2: Reaction of Alkali Metals with Water Observations Flame floats/surface, melts, bubbles/moves/fizz Behaviour NothingPopSplint Blue/baseLitmus SoftestSofterSoftHardness.

ObservationsObservations

Flamefloats/surface, melts, bubbles/moves/fizz

Behaviour

NothingPopSplint

Blue/baseLitmus

SoftestSofterSoftHardness

Shiny / LustreAppear

KNaLi

Page 3: Reaction of Alkali Metals with Water Observations Flame floats/surface, melts, bubbles/moves/fizz Behaviour NothingPopSplint Blue/baseLitmus SoftestSofterSoftHardness.

Answers to Questions 1-4Answers to Questions 1-4

3. The outer electron. Because positive and negative charges attract, but this attraction decreases with distance (like magnets).

4. K was most reactive because it’s outer electron is further away and thus easier to remove. Li is least reactive because its outer electron is closer and harder to remove.

1. K was most reactive, Li was least.2. Li Na K

3 p+

4 n0 2 111 p+

12 n0 2 8 1 19 p+

20 n0 2 8 8 1

Page 4: Reaction of Alkali Metals with Water Observations Flame floats/surface, melts, bubbles/moves/fizz Behaviour NothingPopSplint Blue/baseLitmus SoftestSofterSoftHardness.

Answers to Questions 5-7Answers to Questions 5-75. Rb, Cs, or Fr is more reactive

There is not one that is less reactive6. Litmus tested for hydroxide

A flaming splint tested for hydrogen gas7. The K beaker did not react because the

hydrogen was already used up

Page 5: Reaction of Alkali Metals with Water Observations Flame floats/surface, melts, bubbles/moves/fizz Behaviour NothingPopSplint Blue/baseLitmus SoftestSofterSoftHardness.

MisconceptionsMisconceptions3. Electrons are attracted to protons with an electrostatic force,

not magnetism or gravity.4. K is not more reactive than Li because it has more electrons,

it is because it’s outer electron is further from the nucleus.7. CO2 is not a product when a metal burns or when H2 burns,

only when the original substance contains C. In this case H2 was burning and producing H2O. Excess N2 and no H2 (or O2) can explain the splint going out.

Page 6: Reaction of Alkali Metals with Water Observations Flame floats/surface, melts, bubbles/moves/fizz Behaviour NothingPopSplint Blue/baseLitmus SoftestSofterSoftHardness.

ObservationsObservations

Flame (1)floats/surface, melts,

bubbles/moves/fizz (3)Behaviour

Nothing (1)Pop (1)Splint

Blue/base (1)Litmus

Softest (1)SofterSoftHardness

Shiny / Lustre (1)Appear

KNaLi

Mark: /9

Page 7: Reaction of Alkali Metals with Water Observations Flame floats/surface, melts, bubbles/moves/fizz Behaviour NothingPopSplint Blue/baseLitmus SoftestSofterSoftHardness.

Answers to Questions 1-4Answers to Questions 1-4

3. The outer electron (1). Because positive and negative charges attract, but this attraction decreases with distance (like magnets).

4. K was most reactive because it’s outer electron is further away and thus easier to remove. Li is least reactive because its outer electron is closer and harder to remove.(1)

1. K was most reactive, Li was least (1)2. Li Na K

(1) (1)

/6

3 p+

4 n0 2 111 p+

12 n0 2 8 1 19 p+

20 n0 2 8 8 1

(1)

Page 8: Reaction of Alkali Metals with Water Observations Flame floats/surface, melts, bubbles/moves/fizz Behaviour NothingPopSplint Blue/baseLitmus SoftestSofterSoftHardness.

Answers to Questions 5-7Answers to Questions 5-75. Rb, Cs, or Fr is more reactive (1)

There is not one that is less reactive (1)6. Litmus tested for hydroxide (1)

A flaming splint tested for hydrogen gas (1)7. The K beaker did not react because the

hydrogen was already used up (1)

This slide: /5Total: /20

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