Discuss what all the values of w and q should be if a system is exothermic. Then discuss what all the values of w and q should be if a system is endothermic.

In an exothermic reaction, q is negative while w is positive.

In an endothermic reaction, q is positive while w is negative

Explanation:

An Exothermic reaction is one in which the heat content of the system is greater than the heat content of the surroundings. As a result of this, heat (measured by Q) is given off into the surroundings and the surroundings is hotter than than the system. The heat emitted does work against the surroundings, hence the value of work done W is positive.

An endothermic reaction is the opposite of an exothermic reaction.

During an endothermic reaction, the heat content of the reactants is lesser than the heat content of the products. The surroundings then does work on the system , resulting in heat (measured by Q) being absorbed from the surroundings into the system, making the system hotter than than the surroundings. The value of work done W in an endothermic reaction is negative because the system does work against the surroundings.

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).

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.