100 mL of is initially at room temperature (22)C. A chilled steel rod at 2 C is placed in the water. If the final temperature of the system is 21.2 C, what is the mass of the steel bar?

Specific heat of water = 4.18J/g(C)
Specific heat of steel = 0.452J/g(C)

14 answers

heat lost by water = heat gained by steel

(m Cp dT) water = (m Cp dT) steel

mass steel = (m Cp dT) water / (Cp dT) steel
mass steel = (125 g) x (4.18 J/gC) x (22.0-21.1 C) / [(0.452 J/gC) x (21.1 - 2.0 C)] = 54.5 g steel

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molar heat capacity is J/mole C not J/gC

4.18 J/gC x (18.0 g / mole) = 75.2 J/moleC
mass of the steel is not 54.5 g.
I inputed the answer it didn't work. can you please help me
54.5 g steel doesnt work i inputed the answer it was incorrect
heat lost by water + heat gained by steel = 0
massH2O x specificheatH2O x (Tf-Ti) + masssteel x specificheatsteel x (Tf-Ti) = 0
100 x 4.18 x (21.2-22) + masssteel x 0.452 x (21.2-2) = 0
Solve for mass steel. I get about 40 g but you need to solve it exactly. Watch the signs. Post your work if you get stuck. Tf is final T. Ti is initial T.
the answer is 42.4
It would 24.9 grams
(105.5g)(0.5°C)(4.184J)=x(19.5)(0.452)
The answer with 3 sig figs and units is 43.6 g
38.9
I pooped my pants :(
it will be 33.5g
43.6 its 100 g
34.3
the correct answer 23.7 g
To calculate the mass of the steel bar, we can use the equation:

(mass of water)(specific heat of water)(change in temperature of water) = (mass of steel)(specific heat of steel)(change in temperature of steel)

Let's plug in the given values:

(100 g)(4.18 J/g°C)(21.2°C - 22°C) = (mass of steel)(0.452 J/g°C)(21.2°C - 2°C)

Simplifying:

(-83.6 J) = (mass of steel)(-0.452 J/°C)(19.2°C)

Dividing both sides by (-0.452 J/°C)(19.2°C):

mass of steel = (-83.6 J) / [(-0.452 J/°C)(19.2°C)]

mass of steel = 236.73 g

Therefore, the mass of the steel bar is approximately 236.73 g.