The condensation of two units of glucose will produce a dissacharide with the formula $C_{12}H_{22}O_{11}$ which is

Analyze the question: We need a disaccharide (C₁₂H₂₂O₁₁) formed from the condensation of two glucose units.

Concept: Glucose is a monosaccharide with the formula C₆H₁₂O₆. When two monosaccharides join, a glycosidic bond forms and one molecule of water is lost (condensation).

Solution:

2 C₆H₁₂O₆ → C₁₂H₂₂O₁₁ + H₂O

Check: 2 × C₆H₁₂O₆ = C₁₂H₂₄O₁₂. Remove H₂O to get C₁₂H₂₂O₁₁. ✔

Checking the options:

• A. Sucrose: a disaccharide, but it is made from glucose + fructose, not two glucose units.
• B. Maltose: a disaccharide made from glucose + glucose (α-1,4 glycosidic link). ✔
• C. Galactose: a monosaccharide (C₆H₁₂O₆), not a disaccharide.
• D. Mannose: also a monosaccharide (C₆H₁₂O₆).

Answer: B. maltose.

Exam tip: Remember the disaccharide building blocks:

• Maltose = glucose + glucose
• Sucrose = glucose + fructose
• Lactose = glucose + galactose

A quick memory aid is "Maltose = Malt sugar, glucose twice." Also, any disaccharide's formula is always the two monosaccharides minus one H₂O.