Answer:
41.9 g
Explanation:
We can calculate the heat released by the water and the heat absorbed by the steel rod using the following expression.
Q = c × m × ΔT
where,
c: specific heat capacity
m: mass
ΔT: change in temperature
If we consider the density of water is 1.00 g/mol, the mass of water is 125 g.
According to the law of conservation of energy, the sum of the heat released by the water (Qw) and the heat absorbed by the steel (Qs) is zero.
Qw + Qs = 0
Qw = -Qs
cw × mw × ΔTw = -cs × ms × ΔTs
(4.18 J/g.°C) × 125 g × (21.30°C-22.00°C) = -(0.452J/g.°C) × ms × (21.30°C-2.00°C)
ms = 41.9 g
<h2>Hello!</h2>
The answer is: 4.77atm
<h2>Why?</h2>
Since there's a fixed volume, we can use the the Gay-Lussac's Law which stablish a relation between the pressure and the temperature:

<em>P</em> is the volume of the gas
<em>t</em> is the temperature of the gas
<em>k </em>is the proportionality constant
We also have the following equation:

Where:

We are asked to find the pressure in atm, so we must convert 483.73kPa to atm:

Then,

Have a nice day!