20g of water at 30°C was mixed with 40g of water at 75°C. What is the final temperature of the mixture? (specific heat capacity of water
is 4.184 J/g°C).

The temperature of the mixture is 60°C

Explanation:

We can write the energy of water as follows:

E = m×C×T

Where E is energy in Joules, m is mass of water, C is specific heat of water = 4.184J/g°C and T is temperature

Replacing fot both samples:

E = 20g×4.184J/g°C×30°C

E = 2510.4J

E = 40g×4.184J/g°C×75°C

E = 12552J

The total energy of the mixture is 12552J + 2510.4J = 15062.4J

Mass = 60g:

15062.4J = 60g×4.184J/g°C×T

60°C = T

answer: a chemical reaction

explanation:

im not wrong

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.