Question

give an example to show that same gas is envolved when an acid or base reacts with a metal with an necessary chemical equation​

Answer 1

When Metals reacts with Acids then Salt and formation of Hydrogen gas takes place i.e.

Metal + Dilute Acid → Salt + Hydrogen

Dilute acid like HCl, H2SO4 and Metals like Mg, Zn, Fe, Cl, Na etc.

Examples:

$\sf{Mg+HCl\:\rightarrow\:MgCl_2+H_2}$

$\sf{2Al+6HCl\:\rightarrow\:2AlCl_3+3H_2}$

$\sf{Fe+2HCl\:\rightarrow\:FeCl_2+H_2}$

$\sf{Na+H_2SO_4\:\rightarrow\:Na_2SO_4+H_2}$

If we notice, we found that whenever a metal reacts with acid; hydrogen gas is produced.

But if a metal reacts with nitric acid then the formation of water takes place instead of hydrogen gas. (because nitric acid is a strong oxidising agent).

Also, if a Metal reacts with the base then the formation of Hydrogen gas and salt takes place. i.e.

Metal + Base → Salt + Hydrogen gas.

So, the same gas that is involved when an acid or base is Hydrogen gas.

Examples:

$\sf{Al+NaOH\:\rightarrow\:NaAlO_2+H_2}$

$\sf{Zn+NaOH\:\rightarrow\:Na_2ZnO_2+H_2}$

How to check the presence of Hydrogen gas?

When a burning candle is brought near the test tube, it burns with a 'POP' sound. This confirms the presence of hydrogen gas in the test tube.

$\rule{200}2$

Series of metals in the decreasing reactivity is known as Reactivity Series.

→ K = Potassium

→ Na = Sodium

→ Ca = Calcium

→ Mg = Magnesium

→ Al = Aluminum

→ Zn = Zinc

→ Fe = Iron

→ Pb = Lead

→ H = Hydrogen

→ Cu = Copper

→ Hg = Mercury

→ Ag = Silver

→ Au = Gold

Answer 2

$</p><p>\tt{\pink{\underline{\underline {\: When \: A \: Metal \: Reacts \: With \: An \: Acid \: - }}}}$

Metal + Acid → Salt + H2

When A metal reacts with an acid, it's Corresponding Salt Is Formed and Hydrogen Gas Is Evolved.

Some Examples are the reaction of metals like Magnesium, Iron, Zinc etc with acids like HCl, H2SO4 etc.

Magnesium + Hydrochloric Acid → Magnesium Chloride + Hydrogen.

Mg + 2HCl → MgCl2 + H2

It doesn't matter which metal or which acid is used, if there is a reaction we always get hydrogen gas as well as the salt.

However, how quickly the reaction goes depends on the metal used and how high up in the reactivity series it is.

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$</p><p>\tt{\pink{\underline{\underline {\: When \: A \: Metal \: Reacts \: With \: A\: Base / Alkali\: - }}}}$

Metal + Base/Alkali → Salt + H2

Metals react with base to give Metal Salt and Hydrogen Gas

Some examples are reaction of Metals like Sodium and Zinc with bases such as NaOH etc.

Al + NaOH → NaAlO2 + H2

Al + NaOH → NaAlO2 + H2Zn + NaOH → Na2 Zn2 O2 + H2

How quickly the reaction goes depends on the metal used and how high up in the reactivity series it is.

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Noble Metals Like Gold, Silver etc do not react with either Acid Or Base at any condition.