NOTES ON THE ESTIMATION OF CYANOGEN BY SILVER NITRATE

[CONTRIBUTION FROM THE CHEhltCAL

LABORATORY O F

THE UNIVERSITY

O F CALIFORNIA.]

NOTES ON T H E ESTIMATION OF CYANOGEN BY SILVER NITRATE, USING POTASSIUM IODIDE AND AMMONIA A S INDICATORS.' B Y WILLIAMJ. SHARWOOD. Received !d?.rc!l

6 , 1897.

COSTENTS.

EXPERIMESTAL RESULTS. Series

I.

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2.

I'

3. 4.

5. ' I

(' ' l

6. 7. 8. 9. IO.

'(

11.

"

12.

13. 14. ' ' 15. "

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T

Comparison of results of titrating cyanides by silver nitrate with and without t h e use of potassium iodide and ammonia as indicators.. ........................ 407 Effect of varying volume of solution .................. 407 Proportionality of silver nitrate used i n titration t o cyanide present.. .................................... 408 Effect of varying proportions of indicators. ............ 408 Effect of varying temperature.. ....................... 409 Delicacy of indicator .................................. 409 Effect of fixed alkali.. ................................ 413 Effects of various substances, chiefly salts of alkalies.. 414 Effects of the presence of zinc ........................ 418