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added to another of nitrate of lead, a precipitate of a white colour, called phosphate of lead, will be formed. See Lead.

Remark. Native phosphate of lead is found on the lead hills of Scotland, Germany, Carinthea, &c. It is of a greenish colour, and occurs in stalactites, and also in regular shapes. The artificial as well as the native phosphate is soluble in nitric acid, from which the lead is separated by ammonia, and the phosphoric acid by means of lime water. It is composed of 18 acid, and 82 yellow oxyd of lead.

CARBONATE OF LEAD.

· Experiment 1. If a solution of nitrate of lead be mixed with an alkaline carbonate, a white precipitate of carbonate of lead will result. It is composed of 16} acid, 82s yellow oxyd. See Lead.

FLUATE OF LEAD.

Experiment 1. If fluoric acid be combined with oxyd of lead, the result is a white insoluble powder, called fluate of lead.

BORATE OF LEAD.

Experiment 1. If boracic acid be united with oxyd of lead, borate of lead will be formed, which is a white insoluble powder.

Experiment 2. If this compound be melted before the blow pipe, it forms a colourless glass.

ACETATE OF LEAD.

Experiment 1. If oxyd of lead be dissolved in acetic acid, or in vinegar, and the solution evaporated, crystals of super-acetate of lead will result, called also sugar of lead and salt of saturn. See Lead.

Experiment 2. If acetate of lead be dissolved in acetic acid, the compound formed will be super-acetate of lead.

Remark. The crystals of this salt are small needles. It is very soluble in water, forming the lead water of the shops. When distilled it is decomposed, affording acetic acid, and a yellow inflammable liquor : if the heat be continued carbonic acid and carburetted hydrogen gas are formed. It is composed of 26 acid, 58 yellow oxyd, and 16 water.

Experiment 3. If 100 parts of super-acetate of lead be boiled with 150 parts of litharge, a salt will be formed called acetate of lead, which is less soluble in water than the preceding variety, and crystallizes in plates.

Experiment 4. If litharge be dissolved in vinegar, the result is a solution of lead, called Goulard's ex• tract, which contains acetate of lead.

SUCCINATE OF LEAD.

Experiment 1. If oxyd of lead be dissolved in succinic acid, a salt will be formed called succinate of lead, which forms in foliated crystals scarcely soluble in water, but yoluble in nitric acid,

BENZOATE OF LEAD.

Experiment 1. Benzoic acid combined with lead, forms benzoate of lead which is soluble in water and alcohol, and decomposed by heat.

OXALATE OF LEAD.

Experiment 1. When oxyd of lead is combined with oxalic acid, the result is oxalate of lead.

TARTRATE OF LEAD.

Experimens 1. Tartaric acid unites with lead, form

ing tartrate of lead, an insoluble powder containing 37 acid, and 63 yellow oxyd.

CITRATE OF LEAD.

Experiment 1. When citric acid combines with oxyd of lead, the result is citrate of lead, which exists in the form of a white powder, and is difficultly soluble in water.

MALATE OF LEAD.

Experiment 1. If acetate of lead be added to the juice of apples, a precipitate will be obtained, which is malate of lead. See Malic Acid.

ARSENIATE OF LEAD.

Experiment 1. When arsenic acid is combined with lead, the salt called arseniate of lead is formed, which is a white powder, containing 64.3 per cent. of yellow oxyd of lead.

MOLYBDATE OF LEAD. Experiment 1. When molybdate of potash is poured into nitrate of lead, a white precipitate is formed, which is molybdate of lead. See Molybdenum.

Remark. This salt is found native in rhomboidal plates, of a yellow colour, and is composed of 34.7 acid, and 65.3 yellow oxyd.

TUNGSTATE OF LEAD. Experiment 1. When tungstic acid is united with lead, which may be effected by double decomposition, the result is a white powder, called tungstate of lead.

CHROMATE OF LEAD. Experiment 1. If chromate of potash be mixed with

the nitrate or acetate of lead, a yellow coloured preci. pitate will be formed, called chromate of lead, or chromic yellow of the painters. See Chromate of Potash.

Remark. This compound occurs native, crystallized in four sided prisms, and is composed of 34.9 acid, and 65.1 oxyd. Chromate of lead may be decomposed in a crucible by potash, in the proportion of one part of the ore, if it be native, with eight of potash; the mass is to be dissolved in water, the excess of alkali saturated with nitric acid, and the chromate of lead may be reproduced by adding nitrate of lead.

The soluble salts of lead give the following general appearances with these re-agents, viz.

i. Prussiate of potash occasions a white precipitate.

2. Hydro-sulphuret of potash produces a black precipitate; and,

3. Infusion of nut-galls affords a white precipitate.

SECTION XIII.

SALTS OF NICKEL..

NITRATE OF NICKEL.

Experiment 1. If nitric acid be digested on nickel by means of heat, the metal will be dissolved, and form nitrate of nickel, which crystallizes in green rhom. boidal prisms.

Remark. This salt when exposed to the air at first deliquesces, and afterwards falls to powder, and gra: dually loses the whole of its acid. It is composed of 55 acid, 25 oxyd, and 20 water.

MURIATE OF NICKEL.

Experiment 1. If nickel be dissolved in nitro-muriatic acid, the solution will yield on evaporation, crysa tals of muriate of nickel.

Experiment 2. If this salt be heated it loses its water, and sublimes in the state of golden yellow flowers.

Experiment 3. If these flowers be exposed to the air, they become green by absorbing moisture.

Remark. Muriate of nickel is composed of 34 oxyd, 11 acid, and 55 water.

SULPHATE OF NICKEL.

Experiment 1. If sulphuric acid be digested on nickel, a residue will be left, which, when dissolved in water, acquires a green colour, and on evaporation forms six sided prisms, composed of 35 oxyd, 19 acid, and 46 water.

CARBONATE OF NICKEL.

Experiment 1. If nitrate of nickel be decomposed by carbonate of potash, a green powder will precipitate, which is carbonate of nickel, containing 56.4 acid and water, and 43.6 oxyd.

FLUATE OF NICKEL,

1

Experiment 1. Fluoric acid combines with the oxyd of nickel, and forms fluate of nickel, which crystallizes of a green colour.

ACETATE OF NICKEL.

Experiment 1. If acetic acid be digested on oxyd of nickel, acetate of nickel will be formed, which forms crystals of a green colour.

OXALATE OF NICKEL. Experiment 1. When oxalic acid is combined with oxyd of nickel, the result is oxalate of nickel, which is a green powder scarcely soluble in water.

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