Identify the carbon atom numbered from $\mathrm{C}_1^{\prime}$ to $\mathrm{C}_5$ of monosaccharide unit of DNA nucleotide that lacks oxygen atom from -OH group.

What is the oxidation number of carbon in methanal?

Which from following is the most commonly used refrigerant Freon-12?

Which among the following salts turns red litmus blue in its aqueous solution?