Question

The lead-acid storage battery is the oldest rechargeable battery in existence. It was invented in 1859 by French physician Gaston Plante and still retains application today, more than 150 years later. There are two reactions that take place during discharge of the lead-acid storage battery. In one step, sulfuric acid decomposes to form sulfur trioxide and water:


`H_2SO_4 (l) \rightarrow SO_3 (g) + H_2O (l); $\space$ \Delta H = + 113.kJ`
In another step, lead, lead(IV) oxide, and sulfur trioxide react to form lead(II) sulfate:

`Pb(s) + PbO_2 (s) + 2SO_3 (g) \rightarrow 2PbSO_4 (s); $\space$ \Delta H = -775.kJ`
Calculate the net change in enthalpy for the formation of one mole of lead(II) sulfate from lead, lead(IV) oxide, and sulfuric acid from these reactions. Round your answer to the nearest kJ .

Answer 1

Enthalpy of formation to the nearest KJ = -275KJ

Step-by-step explanation:

Enthalpy of formation is the heat change when one mole of a substance is formed from its element in its standard states and in standard conditions of temperature and pressure. it may be positive or negative, if positive, it is an endothermic reaction where the heat content of the product is greater than that of the reactants. and if negative, it is exothermic reaction - where the heat content of the reactants is greater than the products. the enthalpy of formation is measured in Kilo-Joule/Moles (KJ/Mole).

A detailed step by step calculation of the enthalpy of formation of one mole lead (II) sulfate of is attached below.