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Oxidation of Iron

Fe oxided O reduced

2Feº + ³/2 O2 -> Fe2O3

Feº -> Fe³+ + 3eˉ

2Oº + 4eˉ -> 2O²ˉ

Stage 1. Chemical Reactions in life and the Environment

Matter undergoes physical and chemical changes through chemical reactions formed by products and reactants represented in chemical equations. They classify in mass exchange and energy exchange. Mass exchange centrates in neutralization, single displacement, double displacement, decomposition, synthesis, and combustion. energy exhange only takes part on exothermic and endothermic changes.

Obtaining of Cement

The calcium silicate is hydrated and transformed

in other oxide and a base + water.

This face is known as hydration (2C3S + 6H = C3S2H3 + 3CH, 2C2S + 4H = C3S2H3 + CH).

2Ca2 Si O4 (s)+ H2O (l)

---> Ca3 Si2 O7•3H2O(s)+ Ca(OH)2 (s)

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