Look at the following reaction. select the option that best applies to the reaction.
8fe + s8 ⇄ 8fes

eight moles of reactants form eight moles of product.
nine moles of reactants form eight moles of product.
eight moles of products form eight moles of reactants.
this reaction is not at equilibrium.

Nine moles of reactants form eight moles of product.

Explanation:

According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

As the subscripts in front of the chemical formulas represent the moles of the substances.Thus 8 moles of iron reacts with 1 mole of sulfur to give 8 moles of iron sulfide.

quartz

explanation:

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.