Analytical Applications of I-Amidino-2-thiourea. Part III. Gravimetric Determination of Nickel(II)

A new gravimetric method, based on the quantitative precipitation of nickel(II) as Ni (C2H5N4S)2 with amidinothiourea in hot alkaline solution, is proposed for the estimation of nickel. The error and standard devia­tion of the method are ± 0.3% and ± 0.18% respectively. Amongst anions, only cyanide interferes. The inter­ference of cations, except Cu(II) and Hg(II), is removed by using suitable complexing agents. Separation of nickel from copper and mercury and its subsequent determination with amidinothiourea have been achieved. The present method has boon employed to estimate nickel in alloy steel, stainless steel, and cupronickel alloy