A piece of glass is heated to 92.3°C and then placed into a 41.3 g sample of water. The initial temperature of the
water is 18.9°C, and the final temperature of the water is 20.3°C. Calculate the mass of the piece of the glass.
(The specific heat of glass is 0.739 J/g °C.)

The mass of the piece of glass is 3.47 grams

Explanation:

by comparing the thermal heat  of the glass and water we can have mass of glass placed in water.

from the formula,

E=mcp ∅  ( E= change in thermal energy, m= mass, ∅ change in temperature)

by comparing

m1cp1∅1= m2cp2∅2   (mi is mass of water, cp1 specific heat capacity of water,∅2 change in temperature of water)

m2 cp2 and ∅2 is for glass

41.3*4.186*(20.3-18.9)= m2*0.739*92.3

237= m2* 68.2097

m2= 237/68.2097

     = 3.47 gram

the mass of the piece of glass is 3.47 grams.

u i forgot the answer?

it's c. elements are placed in rows based on how may valencies electrons have.