please exam iwant this asap Calculate the work associated with the compression o

Question

please exam iwant this asap

Calculate the work associated with the compression of a ags from 0.750 L to 150 mL at a constant the pressure of 9 atm. -547 J +547 J - 5.4 J + 5.4 J None of the above A 3.00 g sample of an alloy (containing only pb and sn) was dissolved in nitric acid (HNO_3). Sulfuric acid was added to this solution, which precipitated 2.93 g of pbSO_4. Assuming that all of the lead was precipitated, what is the percentage of Sn in the sample (molar mass of pbSO_4 = 303.3 g/mol) 50.0% Sn 38.5% Sn 33.3% Sn 25.0% Sn None of the above Five identical 1.0-L flasks contain the following gases, each at 0 degree C and 1.0 atm. Which gas has the lowest velocity? He N_2 CH_4 H_2. NH_3 An empty balloon has an initial mass of 5.25 g. After pumping it with helium gas the final mass was 5.45 g. The helium density at 0.80 atm and 25 Degree C is 6.5 times 10^-4 g/mL 0.131 g/mL 1.31 times 10^-4 g/ml 0.650 g/mL None of the above

Explanation / Answer

8)
W = -P*(Vf-Vi)
= -9 atm * (0.150 L - 0.750 L)
= 5.4 atm-L

1 atm-L = 101.33 J

so,
W = 5.4*101.33 = 547 J

Answer: b

9)
moles of PbSO4 = mass/molar mass
= 2.93/303.3
=9.66*10^-3 mol

molar mass of Pb = 207.2 g/mol
mass of Pb = number of mol * molar mass
= 9.66*10^-3 * 207.2
= 2 g

mass of Sn = 1 g

mass % of Sn = mass of Sn *100 / total mass
= 1*100/3
=33.3 %
Answer: c

I am allowed to answer only 1 question at a time

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.