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3 years ago

2. How many grams of water can be heated from 20.0 oC to 75oC using 12500.0 Joules?

Chemistry

2 answers:

Katyanochek1 [597]3 years ago

8 0

Q=12500.0 J
t₁=20.0°C
t₂=75°C
c=4200 J/(kg·°C)

Q=cm(t₂-t₁)
m=Q/{c(t₂-t₁)}

m=12500.0/{4200(75-20)}=0.0541 kg = 54.1 g

kenny6666 [7]3 years ago

4 0

Answer;

= 0.054 kg or 54 g

Explanation;

Using the equation; Q = mcΔT where Q is the quantity of heat transferred, m is the mass, c is specific heat of the substance, ΔT is delta T, the change in temperature.

ΔT = 75 - 20 = 55 C.

Solve the equation for m

m = Q/ cΔT

Mass = 12500 / (55 × 4200)

= 0.054 kg or 54 g

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= Molarity × Volume

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= 1.00 mol

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