Concept explainers
1-66 How many calories are required to heat the following (specific heats are given in Table 1-4)?
(a) 52.7 g of aluminum from 100oC to 285oC
(b) 93.6 g of methanol from —35oC to 55oC
(c) 3.4 kg of lead from —33oC to 730oC
(d) 71.4 g of ice from —77oC to —5oC
(a)
Interpretation:
Heat required rise temperature of aluminum from 100 to 285 ° C should be calculated.
Concept Introduction:
Heat required can be calculate using the following formula:
Where, q is heat required,
m is mass of substance in g,
s is specific heat capacity of the substance and,
Answer to Problem 1.66P
The heat required is 2145 cal.
Explanation of Solution
Given Information:
The mass of aluminum is 52.7 g and change in temperature takes place from 100 ° C to 285 ° C. The value of specific heat capacity of Al from table 1-4 is
For aluminum, heat required can be calculated as follows:
(b)
Interpretation:
Heat required rise temperature of methanol from − 35 to 55 ° C should be calculated.
Concept Introduction:
Heat required can be calculate using the following formula:
Where, q is heat required,
m is mass of substance in g,
s is specific heat capacity of the substance and,
Answer to Problem 1.66P
Heat required is 5140 cal.
Explanation of Solution
Given Information:
Mass of methanol is 93.6 g, change in temperature takes place from
For methanol, heat required can be calculated as follows:
(c)
Interpretation:
Heat required to rise the temperature of lead from − 33 to 730 ° C should be calculated.
Concept Introduction:
Heat required can be calculate using the following formula:
Where, q is heat required,
m is mass of substance in g,
s is specific heat capacity of the substance and,
Answer to Problem 1.66P
Heat required is 80420 cal.
Explanation of Solution
Given Information:
Mass of lead is 3.4 kg, change in temperature takes place from -33 to 730 ° C and specific heat capacity from table 1-4 is 0.031
For Lead, heat required can be calculated as follows:
(d)
Interpretation:
Heat required to rise the temperature of ice from 100 to 285 ° C should be calculated.
Concept Introduction:
Heat required can be calculate using the following formula:
Where, q is heat required,
m is mass of substance in g,
s is specific heat capacity of the substance and,
Answer to Problem 1.66P
Heat required is
Explanation of Solution
Given Information:
Mass of ice is 71.4 g, change in temperature takes place from -77 ° C to -5 ° C and specific heat capacity of ice is 0.48
For ice, heat required can be calculated as follows:
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Chapter 1 Solutions
Introduction to General, Organic and Biochemistry
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