Odetermine whether a shiny gold-colored rock is actually gold, a chemistry student decides to measure its heat capacity. she first weighs the rock and finds it has a mass of 4.7 g. she then finds that upon absorption of 57.2 j of heat, the temperature of the rock rises from 25 °c to 57 °c. find the specific heat capacity of the substance composing the rock and determine whether the value is consistent with the rock being pure gold.

The specific heat capacity of the substance composing the rock is and the value is not consistent with the rock being pure gold.

Explanation:

Q = Heat absorbed= 57.2 Joules

m= mass of substance = 4.7 g

c = specific heat capacity = ?

Initial temperature of the rock = = 25.0°C

Final temperature of the rock =  = 57.0°C

Change in temperature ,

Putting in the values, we get:

The specific heat for the rock is and for pure gold the specific heat is , thus the rock is not pure gold.

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante