Tag: chemistry

Questions Related to chemistry

When a metal reacts with water it forms:

chemistry metals reaction of metals reactions of metals chemical properties of metals

  1. alkalies

  2. basic oxide

  3. dilute acid

  4. neutral acid

Show answer
Correct Option: A
Explanation:

Metals react with water to form alkaline metallic hydroxides.
$Ca+{ H } _{ 2 }O\rightarrow Ca\left( OH \right) _{ 2 }\downarrow +{ H } _{ 2 }\uparrow $

Oxides of which of the following metals is reduced by aluminium powder?

chemistry metals reaction of metals reactions of metals chemical properties of metals

  1. Magnesium

  2. Potassium

  3. Chromium

  4. All of the above

Show answer
Correct Option: D
Explanation:

All metal oxides loses oxygen and are therefore reduced. Metals always occur in their oxidized state in ores. In order to convert an ore to its elemental state, it is reduced.

Metals react with oxygen to form:

chemistry metals reaction of metals reactions of metals chemical properties of metals

  1. acids

  2. $H^+$ ions

  3. metal oxides

  4. all of the above

Show answer
Correct Option: C
Explanation:

Metals react with air (oxygen) to form metal oxides. Metals react with oxygen to form basic oxides or amphoteric oxides. 

Metals reacts with water to form $\ {W}$.

chemistry metals reaction of metals reactions of metals chemical properties of metals

  1. $W =$ acidic oxide, carbon dioxide

  2. $W =$ basic oxide, heater

  3. $W =$ metal oxide, hydrogen

  4. $W =$ metal hydroxide, oxygen

Show answer
Correct Option: C
Explanation:

Metals reacts with water to form a metal hydroxide or metal oxides and hydrogen gas.

What are the products formed when zinc reacts with steam?

chemistry metals reaction of metals reactions of metals chemical properties of metals

  1. Zinc hydroxide and oxygen

  2. Zinc hydroxide and hydrogen

  3. Zinc oxide and oxygen

  4. Zinc oxide and hydrogen

Show answer
Correct Option: D
Explanation:

When zinc reacts with steam it produces zinc oxide and releases hydrogen gas.

A metal $M$ does not liberate hydrogen from acids but reacts with oxygen to give a black colour product. Identify black coloured product is:

chemistry metals reaction of metals reactions of metals chemical properties of metals

  1. $MgO$

  2. $CuO$

  3. $FeO$

  4. $ZnO$

Show answer
Correct Option: B
Explanation:

The metal $M$ is copper $(Cu)$ which reacts with oxygen when heated in the air to form black coloured copper(ll) oxide. The reaction can be written as:
$2Cu + O _{2} \rightarrow 2CuO$

$   Mg        +          H _2O   \rightarrow $      

       (cold water)

chemistry metals reaction of metals reactions of metals chemical properties of metals

  1. $MgO + H _2$

  2. $Mg _2O + H _2$

  3. $MgO + H _2O$

  4. The above reaction cannot occur

Show answer
Correct Option: D
Explanation:

Magnesium and zinc do not react with cold water. They form their respective oxides when reacted with hot water.
$   Mg        +          H _2O         \rightarrow           MgO         +       H _2  $
                            (hot water)

Why is sodium stored in kerosene?

chemistry metals reaction of metals reactions of metals chemical properties of metals

  1. It evaporates

  2. It is highly reactive

  3. It burns

  4. All of above

Show answer
Correct Option: B,C
Explanation:

Sodium metal is very reactive. It reacts vigorously with oxygen and water. A lot of heat is generated in this reaction. Hence, it is stored in kerosene.

Metals like K, Na react ______ with cold water whereas Ca reacts_____ with cold water.

chemistry metals reaction of metals reactions of metals chemical properties of metals

  1. Violently, less violently

  2. Mildly, violently

  3. Violently, violently

  4. Mildly, does not react

Show answer
Correct Option: A
Explanation:

Metals like Na, K react violently with cold water to evolve hydrogen gas that catches fire. Ca on other hand, reacts less violently with cold water giving out hydrogen gas which does not catch fire.

What does the pop sound indicate when sodium reacts with cold water?

chemistry metals reaction of metals reactions of metals chemical properties of metals

  1. Release of oxygen

  2. Release of carbon dioxide

  3. Both A and B

  4. Release of hydrogen

Show answer
Correct Option: D
Explanation:

Sodium metal is very reactive. It reacts vigorously with oxygen and water. A lot of heat is generated in this reaction. Hence, it is stored in kerosene. To test for the release of hydrogen gas, place a lighted splint over the reacting metal - if it "pops" then hydrogen is present.