The Elements of Blowpipe Analysis Part 3

With Co(NO_{3})_{2}. Ma.s.s becomes blue upon re-ignition.

2. ~Antimony, Sb_{2}O_{3}.~--Before the Bp. on Ch. In O. F. volatilizes without change. In R. F. is reduced and volatilized. White coating of antimonious oxide deposited on Ch. Blue tinge imparted to flame.

Before the Bp. on Ch. with Na_{2}CO_{3}. Readily reduced. White brittle bead. Very volatile, giving characteristic white coating.

In ignition tube with Na_{2}CO_{3} and Ch. Volatilized.

In flame on platinum wire. Volatilized. Colors flame greenish blue.

With borax bead on platinum wire. In O. F. dissolves to a colorless gla.s.s.

With Co(NO_{3})_{2}.____

3. ~a.r.s.enic, As_{2}O_{3}.~--Before the Bp. on Ch. Very volatile. Strong garlic odor to fumes.

Before the Bp. on Ch. with Na_{2}CO_{3}. Reduced with emission of a.r.s.enical fumes.

In ignition tube with Na_{2}CO_{3} and Ch. Volatilizes, forming a mirror-like deposit of metallic As in the cooler part of tube.

In flame on platinum wire____

With borax bead on platinum wire____

With Co(NO_{3})_{2}.____

4. ~Bis.m.u.th, Bi_{2}O_{3}.~--Before the Bp. on Ch. Yields a coating--orange-yellow when hot, lemon-yellow when cold. The yellow coating usually has a white outline.

Before the Bp. on Ch. with Na_{2}CO_{3}. Easily reduced to metallic bis.m.u.th. Yellow bead brittle, but less so than antimony.

In ignition tube with Na_{2}CO_{3} and Ch.____

In flame on platinum wire____

With borax bead on platinum wire. In O. F. small quant.i.ty dissolves to a clear yellow gla.s.s, which becomes colorless when cold.

With Co(NO_{3})_{2}____

5. ~Cadmium, CdO.~--Before the Bp. on Ch. Gives a coating on the coal.

Reddish-brown when cold. Very volatile.

Before the Bp. on Ch. with Na_{2}CO_{3}. Readily reduced. The metal volatilizes easily, giving the characteristic coating.

In ignition tube with Na_{2}CO_{3} and Ch.____

In flame on platinum wire____

With borax bead. In O. F. dissolves to a clear yellowish bead, colorless when cold.

With Co(NO_{3})_{2}____

6. ~Chromium, Cr_{2}O_{3}.~--Before the Bp. on Ch. No change.

Before the Bp. on Ch. with Na_{2}CO_{3}. Cannot be reduced. Soda sinks in Ch. and a green colored ma.s.s remains.

In ignition tube with Na_{2}CO_{3} and Ch.____

In flame on platinum wire____

~With borax bead.~ Dissolves slowly but colors intensely. Yellow while hot, green when cold.

With microcosmic salt bead. Colors red when hot, green when cold.

With Co(NO_{3})_{2}____

7. ~Cobalt, CoO.~--Before the Bp. on Ch. In O. F. unchanged. In R. F. is reduced to the metal and is magnetic.

Before the Bp. on Ch. with Na_{2}CO_{3}. Reduced to a gray magnetic ma.s.s.

In ignition tube with Na_{2}CO_{3} and Ch.____

In flame on platinum wire____

With borax bead on platinum wire. In O. F. colors very intensely blue, both hot and cold.

With Co(NO_{3})_{2}____

8. ~Copper, CuO.~--Before the Bp. on Ch. Fuses to a black globule, which can be reduced with some difficulty.

Before the Bp. on Ch. with Na_{2}CO_{3}. Readily reduced to metallic bead, which is red in color, hard, malleable.

In ignition tube with Na_{2}CO_{3} and Ch.____

In flame on platinum wire. Colors flame emerald-green.

With borax bead on platinum wire. In O. F. green when hot, blue when cold.

With Co(NO_{3})_{2}____

9. ~Iron, Fe_{2}O_{3}.~--Before the Bp. on Ch. In O. F. unchanged. In R.

F. becomes black and magnetic.