Question

Give three examples of reaction between metals and water ,to show that different metals have different reactivities

Answer 1

Answer:

If iron is placed in water it get rusted.

if sodium is placed in water it get exploded .

It shows that different metals have different reactivities

Answer 2

Hello There!

Let us start from the highest reactivity to the lowest reactivity:

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For this, we have to know the reactivity series

1st grp-

Potassium - Highly Reactive

Sodium

Calcium

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2nd grp-

Magnesium

Alumnium

Zinc

Iron

Lead

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3rd Grp

Hydrogen

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4th Group

Copper

Mercury

Silver

Gold- Not very reactive

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-The order is of decreasing reactivity -

You might see that some reactivity series vary but they are more or less the same. You could use mnemonics to help you remember.

I use the mnemonic- 'Please Stop Calling me a cute zebra, instead try learning how copper saves gold.' This is a mnemonic of another reactivity series but it still works for me. If you want another one, feel free to comment.

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Significance of groups:-

First group- These react with water to form Hydroxides and Hydrogen Gas. These are Highly reactive.

Second Group- These react with water to form Oxides and Hydrogen Gas.

Third Group- Hydrogen doesnt react with water.

Fourth Group-  Doesnt react with Water. Not very reactive.

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The Question has asked for 3 examples of reactions between Metal and Water, to show have different reactivity-

Lets take 1 element each from the first, second and fourth group to show that different metals have different reactivities:

First Group-

Highly Reactive:

Example-

Sodium + Water---> Sodium Hydroxide + Hydrogen

   Na     +   H$H_{2}$ ---> NaOH + $H_{2}$

Balance the Equation using LHS, RHS Method-

  LHS   |     RHS

Na- 1     |  Na-1

H-  2     |  H- 3

O-  1      |  O- 1

Balance H on Both sides to make LHS=RHS.

Check If it is LHS=RHS, if not check and try balancing other Elements.

Finally you will get-

2Na +2$H_{2}$O ----> 2NaOH + 2$H_{2}$

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Second Group:

Use the same method for the second group:

(I wont explain it again, just refer to the first one)

BUT REMEMBER THAT ON REACTING WITH WATER THEY FORM OXIDES UNLIKE THE FIRST GRP!

Here is the final answer-

(I took Alumnium but you can take any of them)

2Al + 3$H_{2} O$ -----> $Al_{2}O_{3}$ + 3$H_{2}$

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Third Group:

No reaction will take place. These elements are less reactive.

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This is the answer...

The three groups show that different metals have different reactivities!

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Thank you!

Please Mark as Brainliest if this was the answer you expected!

It isnt this long but my explanation made it a lot longer!

Thank you again!