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maksim [4K]
2 years ago
6

A 2.50 g sample of zinc is heated, and then placed in a calorimeter containing 65.0 g of water. Temperature of water increases f

rom 20.00 oC to 22.50 oC. The specific heat of zinc is 0.390 J/g oC. Assuming no heat loss, what was the initial temperature of the zinc metal sample?
Chemistry
1 answer:
swat322 years ago
6 0

718.65 degrees is the initial temperature of the zinc metal sample.

Explanation:

Data given:

mass of zinc sample = 2.50 grams

mass of water  = 65 grams

initial temperature of water = 20 degrees

final temperature of water = 22.5 degrees

ΔT  = change in temperature of water is 2.50 degrees

specific heat capacity of zinc cp= 0.390 J/g°C

initial temperature of zinc sample = ?

cp of water = 4.186 J/g°C

heat absorbed = heat released (no heat loss)

formula used is

q = mcΔT

q water = 65 x 4.286 x 2.5

q water = 696.15 J

q zinc = 2.50 x 0.390 x (22.50- Ti)

equating the two equations

696.15 = - 22.50+ Ti

Ti = 718.65 degrees is the initial temperature of zinc.

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Explanation:

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We have :

Enthalpy changes of formation of following s:

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The equation for the enthalpy change of the given reaction is:

\Delta H_{rxn} =

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6 0
2 years ago
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Answer:

The NMR spectrum that corresponds best to p-bromoaniline  is the one that is attached in the image below.

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4 0
2 years ago
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