percent yield, molecular weight and mass

Question

1. What is the percent yield of a reaction between 25.0 mL of 0.541 M silver nitrate and 10.0 mL of 3.00 M hydrobromic acid (HBr) if 1.31 grams of silver bromide are produced?

2. What mass of Neon gas is required to fill an "OPEN" sign if the tube has a volume of 669.1 mL and is filled at STP. Assume ideal gas behavior, and that the gas filling the sign is 100% neon.

3. Determine the mass of excess reagent remaining after 10.0 mL of 2.50 M sodium hydroxide reacts with 23.8 mL of 1.00 M calcium chloride.

4.What is the molecular weight of a hypothetical compound in the following experiment, assuming ideal gas behavior?

The mass of a 250 mL flask under vacuum weighs 105.000 grams. The flask is filled to 500 torr with the unknown gas, and the flask weighs 105.958 grams afterward. The reaction was completed under isothermal conditions at 22.3 degrees celsius.

Answer 1

Follow the equations:

AgNO3 + HBr = AgBR + HNO3

Well,

Everything is 1:1 with the mole ratio.

You should determine moles before moving into the calculation.

In other words, find the "theoretical yield" and then use the experimental data to determine "percent yield" by taking the difference between the actual and theoretical and dividing by the theoretical.

This ratio should be multiplied by 100 to get the percent yield.