CHEMISTRY HELP!!! Chemical Equations

How dies one identify the products when writing out chemical equations, is it entirely memory or is their some technique of figuring out the resulting products.

E.g. Suggest an equation for the reaction of TeCl4 with water? How would i go about this?

Original post by Paranoid_Glitch

How dies one identify the products when writing out chemical equations, is it entirely memory or is their some technique of figuring out the resulting products.

E.g. Suggest an equation for the reaction of TeCl4 with water? How would i go about this?

This falls under the umbrella of periodicity, i.e. recognising patterns within the periodic table.

Tellurium is in group 16 of the periodic table (old group 6) and you would predict similar chemistry for tellurium as sulfur.

Most of the main group chlorides are covalent, particularly in higher oxidation states and hydrolysed by water to give hydrogen chloride gas and oxides or oxyacids in which the oxidation state is maintained.

Phosphorus, for example in group 15 has two chlorides, PCl₃ and PCl₅ which are both hydrolysed by water to give phosphoric(III) and phosphoric(V) acids respectively.

In group 14, silicon tetrachloride is hydrolysed to give silicic acid and hydrogen chloride.

So I would predict that tellurium(IV) chloride would hydrolyse to give HCl and telluric(IV) acid, H₂TeO₃.

From this point forward you just have to construct the equation:

TeCl₄ + 3H₂O --> H₂TeO₃ + 4HCl

Reply 2

Paranoid_Glitch

OP

19

Original post by charco

This falls under the umbrella of periodicity, i.e. recognising patterns within the periodic table.

Tellurium is in group 16 of the periodic table (old group 6) and you would predict similar chemistry for tellurium as sulfur.

Most of the main group chlorides are covalent, particularly in higher oxidation states and hydrolysed by water to give hydrogen chloride gas and oxides or oxyacids in which the oxidation state is maintained.

Phosphorus, for example in group 15 has two chlorides, PCl₃ and PCl₅ which are both hydrolysed by water to give phosphoric(III) and phosphoric(V) acids respectively.

In group 14, silicon tetrachloride is hydrolysed to give silicic acid and hydrogen chloride.

So I would predict that tellurium(IV) chloride would hydrolyse to give HCl and telluric(IV) acid, H₂TeO₃.

From this point forward you just have to construct the equation:

TeCl₄ + 3H₂O --> H₂TeO₃ + 4HCl

Why H2TeO3 and not H2TeO4? SO3 hydrolyses to H2SO4?