Given that
2al(s)+3/2o2(g)> al2o3(s) deltahrxn=-1601kj/mol
and
2fe(s)+3/2o2(g)> fe2o3(s) deltahrxn=-821kj/mol
calculate the standard enthalpy change for the following reaction.
2al(s)+fe2o3(s)> 2fe(s)+al2o3(s)
enter your answer in scientific notation.

Answerthis solution will not form a precipitateexplanationsolubility equilbrium:         pbf₂(s)  ⇄ pb²⁺(aq) + 2 f⁻(aq)the solubility product expression is    (we exclude solids from the equilibrium expression).now suppose we have the trial ion product q, which we can define as    then, we can interpret  q as the product of the concentration of the ions that we have and ksp as the product of the ion concentrations that are needed to form a saturated solution.if q > ksp, then that implies that there will be a surplus of ions that exceed the amount that is required to form a saturated solution. a precipitate will then form (the precipitate continually  forms until the surplus ions are removed and q is decreased to ksp's value).if q = ksp, the saturated solution that forms is barely saturated and the precipitate will be minimal.if q < ksp, then the ion concentration will not be enough to form a saturated solution (so no precipitate).using our information, we calculate the trial ion product:     since q = 2.7  × 10⁻⁸ < ksp =  4  ×  10⁻⁸, a precipitate will not form.

Answer ozone (o3) is made of three atoms of oxygen, it is a molecule;

B? i feel like this is a trick  

Answerthe same as;