If the rocket engine contains 1500.0 g of H2O2 and an excess of N2H4, what volume of water vapor will be produced when the rocket fires up to a temperature of 540oC and a pressure of 1.2 atm?
I honestly don't GET this thing, ugh =(
Please Help!!
To calculate the volume of water vapor produced when the rocket fires up, we can use the ideal gas law equation: PV = nRT.
First, let's determine the number of moles of H2O2 in the rocket engine.
1. Convert the mass of H2O2 from grams to moles using its molar mass.
The molar mass of H2O2 = (2 x 1.01) + (2 x 16.00) = 34.02 g/mol
Therefore, the number of moles of H2O2 = 1500.0 g / 34.02 g/mol
Next, since H2O2 is in excess, it will completely react with N2H4 to form water (H2O) and nitrogen gas (N2).
The balanced equation for the reaction is:
N2H4 + H2O2 -> H2O + N2
From the balanced equation, we see that 1 mole of H2O2 produces 1 mole of H2O.
Now, let's calculate the volume of water vapor produced using the ideal gas law equation.
1. Convert the temperature from Celsius to Kelvin.
T = 540°C + 273.15 = 813.15 K
2. Rearrange the ideal gas law equation to solve for V (volume):
V = nRT / P
3. Substitute the values into the equation:
V = (moles of H2O) x (R constant) x (temperature in Kelvin) / (pressure)
R constant = 0.0821 L·atm/(mol·K)
V = (moles of H2O) x (0.0821 L·atm/(mol·K)) x (temperature in Kelvin) / (pressure)
4. Use the number of moles of H2O calculated earlier and substitute the values into the equation:
V = (moles of H2O) x (0.0821 L·atm/(mol·K)) x (temperature in Kelvin) / (pressure)
V = (moles of H2O2 / 1) x (0.0821 L·atm/(mol·K)) x (temperature in Kelvin) / (pressure)
V = (moles of H2O2) x (0.0821 L·atm/(mol·K)) x (temperature in Kelvin) / (pressure)
Substitute the values you have calculated into this equation and you will get the volume of water vapor produced when the rocket fires up.
It's just two problems in 1.
The first one is stoichiometry to find the moles of water vapor; the second part is to use PV = nRT to calcualte the volume
1. Write the equation for the reaction between H2O2 and N2H4. I assume that was done in the problem.
2. Convert g H2O2 to moles. Moles = grams/molar mass.
3. Using the coefficients in the balanced equation, convert moles H2O2 to moles H2O.
4. Now use PV = nRT to calculate volume. Don't forget to change C to Kelvin in the second equation. (K =- 273 + C).