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2 years ago

A 47.35 g mass of copper is heated from 20 degrees celsius to 85 degrees celsius. How many joules were added to accomplish this?

Chemistry

1 answer:

lora16 [44]2 years ago

4 0

Answer:

1185.0 J.

Explanation:

The amount of heat needed to accomplish this process can be calculated using the formula:

<em>Q = m.C.ΔT</em>, where,

Q is the amount of heat needed,

m is the mass of the copper <em>(m = 47.35 g)</em>,

C is the specific heat of Cu<em> (C = 0.385 J/g.°C)</em>,

ΔT is the temperature difference (the final temperature - the initial temperature <em>(ΔT = 85.0 - 20.0 = 65.0 °C)</em>.

<em>∴ The amount of heat needed Q = m.C.ΔT </em>= (47.35 g) (0.385 J/g.°C) (65.0 °C) = 1184.933 J ≅ 1185.0 J.

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Read 2 more answers

1. A gas having the following composition is burnt under a boiler with 50% excess air.

jeka94

The composition of the stack gas are :

$CH_4$ = 0.8713

$C_3H_8$ = 0.0202

CO = 0.107

<h3 /><h3>What is a mole fraction?</h3>

The ratio of the number of moles of one component of a solution or other mixture to the total number of moles representing all of the components.

Assuming 100 g of the stack gas. Calculate the mass of each species in this sample according to their percentages.

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Now calculate the number of moles of each species:

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