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Metals in the middle of the reactivity series, such as iron, will react with acids such as sulfuric acid (but not water at normal temperatures) to give hydrogen and a metal salt, such as iron(II) sulfate: Fe (s) + H 2 SO 4 (l) → FeSO 4 (aq) + H 2 (g) There is some ambiguity at the borderlines between the groups.
When a copper wire is dipped in a silver nitrate solution, copper displaces silver, turning the solution blue and solid silver precipitates out ("silver tree"): Cu + AgNO₃ → Cu(NO₃)₂ + Ag↓ NCSSM video on single displacement reaction Formation of tin crystals as zinc displaces tin, seen under microscope.
Class A metals are metals that form hard acids. [1] Hard acids are acids with relatively ionic bonds. These metals, such as iron, aluminium, titanium, sodium, calcium, and the lanthanides, would rather bond with fluorine than iodine. They form stable products with hard bases, which are bases with ionic bonds. They target molecules such as ...
GCSE Bitesize was launched in January 1998, covering seven subjects. For each subject, a one- or two-hour long TV programme would be broadcast overnight in the BBC Learning Zone block, and supporting material was available in books and on the BBC website. At the time, only around 9% of UK households had access to the internet at home.
The terms saturated vs unsaturated are often applied to the fatty acid constituents of fats. The triglycerides (fats) that comprise tallow are derived from the saturated stearic and monounsaturated oleic acids. [3] Many vegetable oils contain fatty acids with one (monounsaturated) or more (polyunsaturated) double bonds in them.
In 1860, the unexpected appearance of sky-blue and dark red was observed in spectral emissions by Robert Bunsen and Gustav Kirchhoff, leading to the discovery of two alkali metals, caesium and rubidium (dark red). [4] [1] Today, this low-cost method is used in secondary education to teach students to detect metals in samples qualitatively. [2]
HSAB is an acronym for "hard and soft (Lewis) acids and bases".HSAB is widely used in chemistry for explaining the stability of compounds, reaction mechanisms and pathways. It assigns the terms 'hard' or 'soft', and 'acid' or 'base' to chemical species.
Usually, these bases are created by adding pure alkali metals such as sodium into the conjugate acid. They are called superbases, and it is impossible to keep them in aqueous solutions because they are stronger bases than the hydroxide ion (See the leveling effect.) For example, the ethoxide ion (conjugate base of ethanol) undergoes this ...