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4 years ago

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How much thermal energy (q) is required to heat 15.2g of a metal (specific heat=0.397J/C) from 21.0C to 40.3C? Show steps please

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1 answer:

Elena L [17]4 years ago

7 0

Q = ?

Cp = 0.397 J/ºC

Δt = 40.3 - 21.0<span> => 19.3</span><span> ºC</span>

m = 15.2 g

Q = m x Cp x Δt

Q = 15.2 x 0.397 x 19.3

Q ≈ 116.46 J

<span>hope this helps! </span>

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<u>Answer:</u> The theoretical yield and percent yield of chromium (III) oxide is 434.72 grams and 92.6 % respectively.

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To calculate the number of moles, we use the equation:

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Now, calculating the mass of chromium (III) oxide from equation 1, we get:

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Putting values in equation 1, we get:

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