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3 years ago

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Consider the reaction: 2 HCl(aq) + Ba(OH)2(aq) BaCl2(aq) + 2 H2O(l); H = –118 kJ. Calculate the change in temperature when 50.

0 mL of 0.20 M HCl(aq) and 50.0 mL of 0.10 M Ba(OH)2(aq) are mixed together. The density ofthe solution is 1.00 g/mL and Solution= 4.184 J/g-°C

1 answer:

Alborosie3 years ago

6 0

Answer:

ΔT = 1,41°C

Explanation:

For the reaction:

2HCl(aq) + Ba(OH)₂(aq) → BaCl₂(aq) + 2 H₂O(l); ΔH = –118 kJ.

If moles of reaction are:

HCl:

0,0500L×0,20M = 0,01moles

Ba(OH)₂:

0,0500L×0,10M = 0,005moles

The heat produced is:

0,005mol×-118 kJ/mol = -0,59 kJ = -590 J

The temperature increasing is:

Q = -C×m×ΔT

Where Q is heat (-590 J), m is mass of solution (100mL = 100g -density of 1,00g/mL) and ΔT is change in temperature.

Replacing:

-590J = -4,184J/g°C×100g×ΔT

<em>ΔT = 1,41°C</em>

<em></em>

I hope it helps!

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