Calculate the work done when 70.0g of tin dissolves in excess acid at 3.00 atm and -15.0 C.

Sn(s)+2H^+(aq) -> Sn^2+(aq)+H2(g)

Assume ideal gas behavior.

Any ideas? I've come up with a few different answers and can't come to a conclusion.

I see the following energies involved:
1) tHe ionization energy of Sn
2) the ionization energy of H+
3) the energy of formation of H2(g)

On 1) make certain the data reflects solid to aq. All of those ought to be standard table look ups. I don't have my Merck or CRC handy.

0J

To calculate the work done when 70.0g of tin dissolves in excess acid, you first need to determine the number of moles of tin that are reacting. Use the molar mass of tin (Sn) to convert the mass of tin to moles:

70.0 g Sn * (1 mol Sn / molar mass of Sn) = x moles Sn

Next, we need to calculate the work done by the system. In this case, the system includes the tin (Sn), hydrogen ions (H+), and the hydrogen gas (H2) being formed.

The work done can be calculated using the formula:

Work = -P * ΔV

Where P is the pressure and ΔV is the change in volume.

In this case, the volume change comes from the hydrogen gas being formed. According to the balanced chemical equation, every 1 mole of tin reacts to produce 1 mole of hydrogen gas. So, the moles of hydrogen gas formed will be equal to the moles of tin used.

Next, we need to determine the change in volume. To do this, we can assume ideal gas behavior and use the ideal gas law equation:

PV = nRT

Where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature.

Since the temperature is given in Celsius, you need to convert it to Kelvin:

T(K) = T(°C) + 273.15

Now, let's substitute the values into the ideal gas law equation:

(3.00 atm) * ΔV = (x moles H2) * (0.0821 L * atm / K * mol) * (-15.0 °C + 273.15 K)

Simplify the equation:

ΔV = (x moles H2) * (0.0821 L * atm / K * mol) * (-15.0 °C + 273.15 K) / (3.00 atm)

Now, we can substitute the value of x moles H2 with the moles of Sn calculated earlier.

ΔV = (moles Sn) * (0.0821 L * atm / K * mol) * (-15.0 °C + 273.15 K) / (3.00 atm)

Finally, calculate the work done:

Work = -P * ΔV
Work = -(3.00 atm) * [(moles Sn) * (0.0821 L * atm / K * mol) * (-15.0 °C + 273.15 K) / (3.00 atm)]

Simplify the equation and calculate the numerical value. Note that the negative sign indicates work done by the system (exothermic reaction):

Work = -[(moles Sn) * (0.0821 L * atm / K * mol) * (-15.0 °C + 273.15 K)]

Evaluate this equation to get the final calculated value for the work done.

To calculate the work done, we need to consider the change in energy in the system. In this case, the work done is equal to the change in Gibbs free energy (ΔG).

To calculate ΔG, we can use the equation:

ΔG = ΔH - TΔS

where ΔH is the change in enthalpy, T is the temperature in Kelvin, and ΔS is the change in entropy.

First, let's calculate the change in enthalpy (ΔH). Since the reaction involves the dissolution of tin and the formation of hydrogen gas, we need to consider the enthalpies of these reactions.

The enthalpy of ionization of tin (Sn) can be obtained from reference tables. Similarly, the enthalpy of ionization of hydrogen (H+) can also be found in reference tables. These values represent the energy required to convert one mole of the respective substances from their standard states to ions in solution.

Next, we need to consider the energy of formation of hydrogen gas (H2). This value can also be found in reference tables and represents the energy change when one mole of H2 is formed from its elements in their standard states.

Once we have these values, we can calculate the change in enthalpy (ΔH) by summing the energies of the relevant reactions:

ΔH = enthalpy of ionization of Sn + enthalpy of ionization of H+ - energy of formation of H2

Now, let's calculate the change in entropy (ΔS). Since the reaction involves the formation of gas (H2), we need to consider the change in entropy associated with this process. The change in entropy can be obtained from reference tables.

With ΔH and ΔS calculated, we can determine the change in Gibbs free energy (ΔG) using the equation mentioned earlier:

ΔG = ΔH - TΔS

Finally, we can substitute the values given in the question into the equation to obtain the work done.

Remember to convert the temperature from Celsius to Kelvin by adding 273.15.

I hope this explanation helps you calculate the correct answer.