(a) calculate the total volume (in liters) of air an adult breathes in a day. (b) in a city with heavy traffic, the air contains 2.1 x 10^-6l of carbon monoxide (a poisonous gas) per liter. calculate the average daily intake of carbon monoxide in liters by a person.

a) V air/day = 8640 L air  an adult breaths / day

b) 0.0181 L CO intake a person / day

Explanation:

a) one average person has 12 breaths for min:

in each breath it take an average  of 500 mL on air.

⇒ 12 breath / min * 500mL air / breath = 6000 mL air / min

the average air volume per day of a person is:

⇒ Vair/day = 6000 mL air / min * (60 min / h) * ( 24 h / day ) = 8640000 mLair / day * ( L / 1000 mL)

⇒ V air / day = 8640 L / day

b) 2.1 E-6 L CO / L air * 8640 L air / day = 0.0181 L CO / day

a. a primary source combines several different accounts of an event. b. a primary source generally benefits from having been written after an event.

explanation:

answer: the enthalpy of the overall chemical reaction is +87.88 kj or +88 kj.

according to hess's law, the overall enthalpy of a reaction is the difference between the sum of enthalpy values of all the products and the sum of enthalpy values of all the reactants.

δh(reaction) = ∑nδh(products) - ∑nδh(reactants)

δh(reaction) = [δh +δh] - [δh]

δh(reaction) = [1(-287.02) + 1(0) ] - [1(-374.9)] kj = +87.88 kj

here, δh (pcl3) = -287.02 kj, δh(cl2) = 0, δh(pcl5) = -374.9 kj

therefore, enthalpy of the overall reaction is +87.88 kj or +88 kj.