Two systems with heat capacities 19.9 j mol-1 k-1 and 28.2 ] mol 1 k-1 respectively interact thermally and come to an equilibrium temperature of 300c. if the initial temperature of system 1 was 450c, what was the initial temperature of system 2 in °c? you may assume that the total energy of the combined systems remains constant

Answer : The initial temperature of system 2 is,

Explanation :

In this problem we assumed that the total energy of the combined systems remains constant.

The mass remains same.

where,

= heat capacity of system 1 = 19.9 J/mole.K

= heat capacity of system 2 = 28.2 J/mole.K

= final temperature of system =

= initial temperature of system 1 =

= initial temperature of system 2 = ?

Now put all the given values in the above formula, we get

Therefore, the initial temperature of system 2 is,

percent abundance for cu-63 can be shown as:

63 x + 65 (1-x) = 62.9296

65 - 62.9296 = 2 x

x = 1.035

thus, percent abundance for cu-63 is 1.035

percent abundance for cu-65 can be shown as:

63 x + 65 (1-x) = 64.9278

65 - 64.9278 = 2 x

x = 0.0361

thus, percent abundance for cu-63 is 0.0361

the mass spectrum of cu-63 showing the intense peak as, this isotope is found in nature more abundantly around 92.38 % in comparison to cu-65 which is found 62.58 % naturally