115012016 12:29 PM Gradeb Print i Calculator-d Periodic Table Question 12 of 19

Question

115012016 12:29 PM Gradeb Print i Calculator-d Periodic Table Question 12 of 19 ncorrect Map In a constant-pressure calorimeter, 55.0 mL of 0.320 M Ba(OH)2 was added to 55.0 mL of 0.640 M HCI. The reaction caused the temperature of the solution to rise from 22.54 to 26.90 . If the solution has the same density and specific heat as water (1.00 g/mL and 4.184 Jig K, respectively), what is reaction (per mole of H20 produced)? Assume that the total volume is the sum of the individual volumes. d specific heat as water (1.00 g/mL and 4.184 J/g K, respectively), what is AH for this Number kJ/ mol H,O

Explanation / Answer

Solution :-

Lets calculate the moles of Ba(OH)2 and HCl

Moles of Ba(OH)2 = molarity * volume

                                  = 0.320 mol per L * 0.055 L

                                  = 0.0176 mol

Molarity of the HCl is twice the molarity of the Ba(OH)2 and volume is same

So the moles of HCl = 0.0176 * 2 = 0.0352 mol

Reaction equation

Ba(OH)2 + 2HCl ------ > BaCl2 + 2H2O

Lets calculate the moles of the H2O that can be formed

0.0176 mol Ba(OH)2 * 2 mol H2O/ 1 mol Ba(OH)2 = 0.0352 mol H2O

now lets calculate the amount of heat produced by reaction

mass of solution = 55 g +55 g = 110 g because density is 1g/ml

delta T = 26.90 C – 22.54 C = 4.36 C

q= m*s*delta T

= 110 g * 4.184 J per g C * 4.36 C

= 2007 J

So the amount of heat given by the reaction is 2007 J but since reaction is exothermic so we write it as

-2007 J

Now lets convert it to the

kJ per mol water

(-2007 J * 1 kJ / 1000 J)*( 1 mol / 0.0352 mol H2O) = -57.02 kJ/ mol H2O

So the answer is

Delta H = -57.02 kJ/mol H2O

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

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