If a 200-mm test tube is substituted for the gas buret in a Aluminum Analysis experiment ( collect H2 from the sample ,and measure its pressure and volume ,
then, find out its number of moles and Aluminum's percent in the sample) ,indicate the additional measurements you will make .
To determine the number of moles of hydrogen gas and the percent of aluminum in the sample, you will need to make additional measurements and perform calculations. Here are the steps you can follow:
1. Collecting hydrogen gas:
- Set up the experiment as you would with the gas buret.
- Instead of using a gas buret, use a 200-mm test tube to collect the hydrogen gas produced.
- Ensure that the test tube is securely sealed to prevent any gas from escaping.
- Maintain appropriate temperature and pressure conditions during the collection process.
2. Measuring the pressure and volume of hydrogen gas:
- Use a pressure sensor or manometer to measure the pressure of the hydrogen gas inside the test tube.
- Note down the pressure reading, ensuring it is in a unit such as atmospheres (atm) or pascals (Pa).
- Measure the volume of the test tube, typically in milliliters (mL).
3. Calculating the number of moles of hydrogen gas:
- 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 in Kelvin.
- Rearrange the equation to solve for n: n = PV / RT.
- Substitute the values you measured for pressure (in atm), volume (in liters), and temperature (in Kelvin) into the equation.
- The resulting value will give you the number of moles of hydrogen gas.
4. Determining the percent of aluminum in the sample:
- We need to compare the number of moles of hydrogen gas to the number of moles of aluminum in the sample.
- Use the balanced chemical equation for the reaction between aluminum and hydrogen to determine the stoichiometry.
- Based on the stoichiometry, determine the mole ratio between aluminum and hydrogen gas.
- Divide the number of moles of hydrogen gas by the mole ratio to get the number of moles of aluminum.
- Calculate the percent of aluminum by dividing the moles of aluminum by the total moles in the sample and multiplying by 100.
Remember to record all measurements accurately and use appropriate units throughout the calculations.