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34
1817
Octr. 1
Sol of Ammonia dissolves with heat much more white Arsenic
than water does but on cooling almost the whole of the Arsenic is thrown down
though the liquor be strongly alkaline Ammonia therefore when the affinities are
increases by temperature does export evince a degree of chemical attraction for Arsenic
independant of that of its water but at low temperatures this power is almost lost &
gives way to attraction of cohesion
- [Chloriodine] added to potash is decomposed the chlorine combines
with the alkali liberating the iodine in [solid form] it [xxxxxx]combines with other portion
of the alkali but more slowly the resulting bodies are [combinate] of chlorine & iodine
with Potassium & [ chlorine ] & iodine each with oxygen & potassium
- Will chromic acid combine with the oxide of Chrome so as
to form a neutral & well defined salt?
- Muriate of chromium is no test for [Lead] the chromium
being only in the state of oxide
Muriate of chromium is precipitate green (dusky) by [sulphate]
of Ammonia - blue by precipitate of potash |resoluble in [excess of precipitate] | - [xxxxxxxx] by tincture of galls
-- green by Ammonia -- lighter green by Carbonate of Ammonia --
Hydriodate of potash pea green - Hydroidic acid greenish yellow --
not precipitated by chromate of potash
Chromate of potash does not precipitate [sulphuret] of Ammonia
nor [xxxxxxxx] of potash - nor tincture of galls - Ammonia - or carb of Ammonia
nor by iodine of its compounds
- Muriate of chromium very soluble - of a fine green colour
slightly reddens [littmus] but not [then] vegetable blues - evaporated to dryness & heated
becomes chlorid which with water is reconverted into muriate
Sulphate of [ Soda ] added to muriate of Chrome thrown down [a]

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Ammonia

Symbol/formula: NH3

An inorganic chemical compound of nitrogen and hydrogen. Ammonia is a colourless gas with a distinct pungent smell.

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Arsenic

Symbol/formula: As

Arsenic occurs in many minerals, usually in combination with sulphur and metals, but also as a pure elemental crystal. Arsenic is a metalloid.

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Potash

An alkaline substance consisting largely of impure potassium carbonate. In October 1807, Davy decomposed potash using electricity, revealing the previously unknown element potassium.

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Chlorine gas

Symbol/formula: Cl

Davy named chlorine in 1810 and insisted it was an element and not a compound.

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Iodine

Symbol/formula: I

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Potassium

Symbol/formula: K

A silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure.

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Oxygene

Symbol/formula: O

Now known as oxygen. Oxygen is a colourless, odourless, tasteless gas essential to living organisms.

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Chromium

Symbol/formula: Cr

A chemical element; it is a steely-grey, lustrous, hard, and brittle transition metal.

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Ammonium carbonate

Symbol/formula: (NH4)2CO3

Ammonium carbonate is a salt, also known as baker's ammonia.

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Soda

An alkaline substance obtained from the ashes of marine or salt-impregnated plants, especially species of Salsola. Davy decomposed soda to reveal its elemental sodium.