718.65 degrees is the initial temperature of the zinc metal sample.
Explanation:
Data given:
mass of zinc sample = 2.50 grams
mass of water = 65 grams
initial temperature of water = 20 degrees
final temperature of water = 22.5 degrees
ΔT = change in temperature of water is 2.50 degrees
specific heat capacity of zinc cp= 0.390 J/g°C
initial temperature of zinc sample = ?
cp of water = 4.186 J/g°C
heat absorbed = heat released (no heat loss)
formula used is
q = mcΔT
q water = 65 x 4.286 x 2.5
q water = 696.15 J
q zinc = 2.50 x 0.390 x (22.50- Ti)
equating the two equations
696.15 = - 22.50+ Ti
Ti = 718.65 degrees is the initial temperature of zinc.
