A 12.6 g block of a metal intially at a temperature of 94.0 °C is added to a 100.0 g sample of water intially at 21.0 °C. If the final temperature of the water is 25.1 °C, determine the specific heat of the metal. Write all equations or formulas you use, and show as much of your work as you can.

The specific heat of the metal is 0.0482 joules per gram-Celsius.

Explanation:

Block of metal is cooled by adding water and thermal equilibrium is reached. According to the First Law of Thermodynamics and by supposing the absence of energy and mass interaction of the system with surroundings, the change in the energy of the system is represented by:

Where and are the changes in internal energies of the block of metal and water, measured in joules.

The expression described above is now extended by applying the definition of internal energy for constant mass systems:

Where:

, - Masses of the block of metal and water, measured in grams.

, - Specific heats of the block of metal and water, measured in joules per gram-Celsius.

, - Initial temperatures of the block of metal and water, measured in Celsius.

, - Final temperatures of the block of metal and water, measured in Celsius.

The specific heat of the metal is cleared in the equation:

If , , , , and , the specific heat of the metal is:

The specific heat of the metal is 0.0482 joules per gram-Celsius.

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."