1. the specific heat capacity of iron is 0.461 j g–1 k–1 and that of titanium is 0.544 j g–1 k–1. a sample consisting of a mixture of 10.0 g fe and 10.0 g ti at 100.0 ºc loses 200. j of heat to the environment. what is the final temperature of the sample?

The answer is 80,1 °C

Explanation:

Let´s start from the mass of the sample and the heat capacities:

First of all, we must calculate an average heat capacity. That's because we have a mixture and it is unknown the heat capacity of the whole sample.

The way we should do this calculation is as follows:

(1)

For example, the mass fraction of Fe is simply:

(2)

If you combine the equations (1) and (2) you have:

(3)

Once calculated the average heat capacity we can solve the problem taking into account the corresponding equation:

(4)

Remember that:

Q: Heat gained or lost

m: Mass of the sample you want to analize

: The value obtained in equation (3)

: Final temperature of the sample

: Initial temperature of the sample

Now we must replace the problem data in equation (4)

Take into account:

Heat gained in a system have a positive valueHeat lost in a system have a negative valueIn this problem the sample loses 200 J, for this reason The mass of the whole sample is: 10g of Fe + 10g of Ti = 20g of sampleThe temperatures must be in absolute units of temperature (these are: rankine or kelvin)The initial temperature of the system is 100°C or 373K

Now we are ready to use equation (4):

(5)

It is clear that the unknown in equation (5) is

The next step is to calculate . Don't forget the signs; these are important.

Key concept: Since the system is loosing heat, the final temperature of the system ( ) should be lower than the initial temperature ( )

It dont even matter because at the end of thre day we gone life like it ius s

Matter- occupies space and possesses rest massno matter is the opposite