The calorie (4.184 J) was originally defined as the quantity of energy required to raise the temperature of 1.00 g of liquid water 1.00°C. The British thermal unit (Btu) is defined as the quantity of energy required to raise the temperature of 1.00 lb of liquid water 1.00°F.
(a) How many joules are in 1.00 Btu ( 1 lb = 453.6 g; a change of 1.0∘C=1.8∘F?
(b) The therm is a unit of energy consumption and is defined as 100,000 Btu. How many joules are in 1.00 therm?
(c) How many moles of must be burned to give 1.00 therm of energy? (Assume water forms as a gas.)
(d) If natural gas costs $0.66 per therm, what is the cost per mole of methane? (Assume natural gas is pure methane.)
(e) How much would it cost to warm 318 gal of water in a hot tub from 15.0∘C to 42.0∘C (1 gal = 3.78 L)?

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.

The answer would be true

Do you have any options for this question?