Question #0ce58

1 Answer
Mar 24, 2017

65.6^@"C"65.6C

Explanation:

The key here is the specific heat of gold.

As you know, a substance's specific heat tells you the amount of heat needed in order to increase the mass of "1 g"1 g of that substance by 1^@"C"1C.

In your case, you have

c_"gold" = "0.126 J g"^(-1)""^@"C"^(-1)cgold=0.126 J g1C1

This means that in order to increase the temperature of "1 g"1 g of gold by 1^@"C"1C, you need to supply it with "0.126 J"0.126 J of heat.

Now, John's gold tooth has a mass of "14.7 g"14.7 g. You can use the specific heat of gold to calculate the amount of heat needed to increase the temperature of "14.7 g"14.7 g of gold by 1^@"C"1C

14.7 color(red)(cancel(color(black)("g"))) * "0.126 J"/(1color(red)(cancel(color(black)("g"))) * 1^@"C") = "1.8522 J"""^@"C"^(-1)

So, if you supply "1.8522 J" of heat to "14.7 g" of gold, you will increase its temperature by 1^@"C". This means that the heat absorbed from the hamburger will cause its temperature to increase by

46.5 color(red)(cancel(color(black)("J"))) * overbrace( (1^@"C")/(1.8522 color(red)(cancel(color(black)("g")))))^(color(blue)("for 14.7 g of gold")) = 25.1^@"C"

You now know that the temperature of the tooth increased by 25.1^@"C". You can thus say that the final temperature of the tooth will be

T_"final" = 40.51^@"C" + 25.1^@"C" = color(darkgreen)(ul(color(black)(65.6^@"C")))

The answer is rounded to three sig figs.