Victor-Meyer test is used to distinguish primary, secondary and tertiary alcohols. In this test, first the given alcohol is treated with P/I2 and then with AgNO2 and HNO2. When the NaOH is added to the product obtained, appearance of red colour indicates the presence of primary alcohol, appearance of blue colour indicates the presence of secondary alcohol while no colouration shows the presence of tertiary afeohol. Note: Lucas test is also used to distinguish primary, secondary and tertiary alcohols.