Hydrocarbons

The correct option is (C): Bleaching powder.

Step 1: Types of Bonds in Organic Molecules.
A double bond consists of one sigma bond and one pi bond. It is present between two carbon atoms in some organic molecules. Step 2: Identifying the Molecule with a Double Bond.
Oxygen (O ) contains a double bond between the two oxygen atoms. Ethene (C H ) also contains a double bond. Step 3: Conclusion.
Thus, Oxygen (O ) contains a double bond.

Step 1: Understanding Mild Bases.
A mild base is one that is not very strong in terms of dissociation in water or does not readily accept protons. Step 2: Magnesium Hydroxide as a Mild Base.
Magnesium hydroxide (Mg(OH) ) is a mild base because it is only slightly soluble in water, unlike sodium hydroxide (NaOH) and potassium hydroxide (KOH), which are strong bases. Step 3: Conclusion.
Thus, Magnesium hydroxide (Mg(OH) ) is a mild base.

Step 1: Understanding alkane formula.
Alkanes are saturated hydrocarbons, meaning they contain only single bonds between carbon atoms. The general molecular formula for alkanes is C H , where is the number of carbon atoms in the molecule. Step 2: Specific example - Propane.
For example, C H is propane, an alkane with 3 carbon atoms. This satisfies the general alkane formula C H , where . Step 3: Conclusion. Thus, C H (propane) is an example of an alkane.

1. Addition reaction:
The given reaction is an example of an addition reaction. In this reaction, a molecule of hydrogen ( ) is added to the alkyne (2-butyne) in the presence of a nickel (Ni) catalyst. This leads to the conversion of the alkyne (an unsaturated compound) into an alkane (a saturated compound), n-butane. This is an addition of hydrogen to the carbon-carbon triple bond. 2. Other reactions:
Hydrogenation is a specific type of addition reaction where hydrogen is added to unsaturated compounds, but in this case, the broader term "addition" is more appropriate.
Halogenation involves the addition of halogens, which is not happening here.
Hydrolysis is a reaction with water to break down compounds, not applicable in this case.