Answer:
CaF2
Explanation:
Calcium fluoride is a solid formed by the chemical combination of Calcium (Ca) and Fluorine (F). Two molecules of fluorine (F2) and one molecule of Calcium (Ca) are needed to form the Calcium Fluoride molecule.
An ionic bond is formed between the Calcium and Fluorine atoms i.e. electrons are transferred from calcium atoms to fluorine atoms. The calcium ion is a cation with formula; Ca2+ while fluorine is an anion with formula; F-. Hence, it takes two molecules of Fluorine ion (F-) to form a relatively stable and neutral molecule with 1 molecule of Calcium ion (Ca2+).
It's made up of two different metals bonded together, which expand by different amounts as they heat up. As the temperature changes, the bimetallic strip curves more or less tightly (contracts or expands) and the pointer, attached to it, moves up or down the scale.
For example, at atmospheric corrosion of copper:
2Cu + CO₂ + O₂ + H₂O = CuCO₃*Cu(OH)₂
and disolution of substances of copper in an acid condition:
CuCO₃*Cu(OH)₂(s) + 4HNO₃(aq) = 2Cu(NO₃)₂(aq) + CO₂(g) + 3H₂O(l)
CuCO₃*Cu(OH)₂(s) + 4H⁺ = 2Cu²⁺ + CO₂ + 3H₂O
Answer:
2C(s, graphite)+ 3H₂(g) + ½O₂(g) ⟶ C₂H₅OH(ℓ)
Explanation:
The thermodynamic standard state of elements and compounds is defined as their most stable state at 25 °C and 1 bar
The elements in ethanol, C₂H₅OH, are C, H, and O.
Their most stable states at standard conditions are C₂H₅OH(ℓ), C(s, graphite), H₂(g), and O₂(g)
The equation for the formation of ethanol from its elements is then
2C(s, graphite) + 3H₂(g) + ½O₂(g) ⟶ C₂H₅OH(ℓ)
