Tollen's Test (Silver Mirror)

RCHO + 2Ag(NH3)2+ + 2OH− → RCOO− + 2Ag + 4NH3 + H2O

Tổng quan

Tollens' reagent (silver-ammonia complex) is reduced to metallic silver by aldehydes, producing a silver mirror on the test tube walls. The aldehyde is oxidized to a carboxylate. This test distinguishes aldehydes from ketones, as ketones cannot be easily oxidized. It was historically used for mirror manufacturing.

Người tham gia

Vai trò Chất Hệ số Trạng thái
Sản phẩm Water H₂O 1 (l)
Sản phẩm Silver Ag 2 (s)
Sản phẩm Ammonia NH₃ 4 (aq)

Ví dụ thực tế

The silver mirror test creates a beautiful reflective coating on glass, and this chemistry was actually used to make mirrors commercially.

Tầm quan trọng công nghiệp

Tollens' test is used in organic chemistry for aldehyde identification. Silver mirror manufacturing by chemical reduction is still used for high-quality mirrors.

Tính chất

Loại
Redox
Thuận nghịch
Không
Năng lượng
Tỏa nhiệt
ΔH
-135,0 kJ/mol

Phản ứng liên quan

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Frequently Asked Questions

What is the equation for Tollen's Test (Silver Mirror)?
The balanced equation is: RCHO + 2Ag(NH₃)₂⁺ + 2OH⁻ → RCOO⁻ + 2Ag + 4NH₃ + H₂O.
What type of reaction is Tollen's Test (Silver Mirror)?
Tollen's Test (Silver Mirror) is a redox reaction.
Is Tollen's Test (Silver Mirror) exothermic or endothermic?
Tollen's Test (Silver Mirror) is exothermic (releases energy). The enthalpy change (ΔH) is -135.0 kJ/mol.