Logo
Home Study Material Contact Search
AI Chat FREE
  1. sciences
  2. chemistry
  3. insoluble pbbr2(s) precipitates when solutions of

Insoluble PbBr2(s) precipitates when solutions of Pb(NO3)2(aq) and NaBr(aq) are mixed. Pb(NO3)2(aq) + 2 NaBr(aq) → PbBr2(s)...

Free

80.2K

Verified Solution

Question

Chemistry

Insoluble PbBr2(s) precipitates when solutions of Pb(NO3)2(aq)and NaBr(aq) are mixed.

Pb(NO3)2(aq) + 2 NaBr(aq) → PbBr2(s) + 2 NaNO3(aq) ΔrH° = ?

To measure the enthalpy change, 200. mL of 0.75 M Pb(NO3)2(aq)and 200. mL of 1.5 M NaBr(aq) are mixed in a coffee-cupcalorimeter. The temperature of the mixture rises by 2.44 °C.Calculate the enthalpy change for the precipitation of PbBr2(s), inkJ/mol. (Assume the density of the solution is 1.0 g/mL, and itsspecific heat capacity is 4.2 J/g ∙ K.)

Answer & Explanation Solved by verified expert
3.6 Ratings (463 Votes)

Pb(NO3)2(aq) + 2 NaBr(aq) → PbBr2(s) + 2 NaNO3(aq)

no of moles Pb(NO3)2 = molarity * volume in L

                                    = 0.75*0.2 = 0.15 moles

no of moles of NaBr    = molarity * volume in L

                                     = 1.5*0.2 = = 0.3

0.15 moles of Pb(NO3)2 react with 0.3 moles of NaBr to gives 0.15 moles of PbBr2

total volume = 200+ 200 = 400ml

mass of solution = volume * density

                              = 400*1 = 400g

q = mC deltaT

      = 400*4.2*2.44   = 4099.2 J

     J/mole = 4099.2/0.15   = 27328J/mole = 27.328KJ/mole
Get Answers to Unlimited Questions

Join us to gain access to millions of questions and expert answers. Enjoy exclusive benefits tailored just for you!

Membership Benefits:
  • Unlimited Question Access with detailed Answers
  • Zin AI - 3 Million Words
  • 10 Dall-E 3 Images
  • 20 Plot Generations
  • Conversation with Dialogue Memory
  • No Ads, Ever!
  • Access to Our Best AI Platform: Flex AI - Your personal assistant for all your inquiries!
Become a Member

Other questions asked by students

Finance
1.2K views

A pension fund manager is considering three mutual funds. The first is a stock fund, the...

Basic Math
1.2K views

An environmentalist wants to find out the fraction of oil tankers that have spills each month. Step...

Electrical Engineering
1.2K views

1(a) Discuss the differences that exist between sources of electrostatic, magnetostatic and electromagnetic fields. Successively, with the...

Advance Math
1.2K views

Suppose f maps a closed and bounded set D to the reals is continuous. Then the...

Physics
1.2K views

9 An object is made by removing a D shaped chunk from a cylinder of...

Basic Math
1.2K views

A hoodlum throws a stone vertically downward with an initial speed of 10 0 m...

Statistics
1.2K views

Homework 4 4 Score 0 8 0 8 answered Question 2 Assume that a procedure...

Statistics
1.2K views

Question 8 of 32 worth 2 points In hypothesis testing it is possible to reject...

Accounting
1.2K views

Contrast the economic resources measurement focus and the current financial resources measurement focus with regard...

Accounting
1.2K views

Below is a list of transactions that took place in the first month of operations...

Accounting
1.2K views

NPV and IRR Each of the following scenarios is independent. All cash flows are after-tax...

Accounting
1.2K views

This case will enable you to practice conducting planning and substantive analytical procedures for accounts...