How do I set this up? What formula do I use? Will you please help me?

How many liters of ammonia at STP are produced when 10 g of hydrogen is combined with nitrogen?

This is a regular stoichiometry problem. Most of them are worked the same way. Print this out and memorize it.

1. Write the equation and balance it.
2. Convert grams of what you have (in this case 10 g H2) to moles. moles = grams/molar mass.
3. Using the coefficients in the balanced equation, convert moles of what you have (in this case moles H2) to moles of what you want (in this case moles NH3).
4. Now convert moles NH3 to liters. There are 22.4 L/mol; therefore, moles NH3 x 22.4 = liters NH3 at STP. Many problems ask for grams, so this last step for them would be grams = mols x molar mass.

To calculate the number of liters of ammonia produced, we need to use the stoichiometry of the balanced chemical equation and the ideal gas law. Here's the step-by-step process to get the answer:

1. Write the balanced chemical equation:
N₂ + 3H₂ → 2NH₃

2. Determine the molar mass of hydrogen (H₂) and ammonia (NH₃):
Molar mass of H₂ = (2 × atomic mass of hydrogen) = 2 × 1 g/mol = 2 g/mol
Molar mass of NH₃ = (atomic mass of nitrogen) + (3 × atomic mass of hydrogen) = 14 + 3 × 1 = 17 g/mol

3. Convert the given mass of hydrogen (10 g) into moles:
Moles of H₂ = (given mass of H₂) / (molar mass of H₂) = 10 g / 2 g/mol = 5 mol

4. Based on the stoichiometry of the balanced chemical equation, we know that:
1 mole of N₂ reacts with 3 moles of H₂ to produce 2 moles of NH₃.

Since we have 5 moles of H₂, we need to determine the corresponding moles of NH₃ produced:
Moles of NH₃ = (moles of H₂) × (2 moles of NH₃ / 3 moles of H₂) = 5 mol × (2/3) = 10/3 mol

5. Use the ideal gas law to convert moles of NH₃ to volume at STP (Standard Temperature and Pressure):
The ideal gas law equation is: PV = nRT, where P is pressure, V is volume, n is moles, R is the ideal gas constant, and T is temperature.

At STP, the temperature (T) is 273 K, and the pressure (P) is 1 atm.
The ideal gas constant (R) is 0.0821 L·atm/(mol·K).

Rearrange the ideal gas law equation to solve for V (volume):
V = (nRT) / P

Substitute the known values:
V (volume of NH₃) = (moles of NH₃) × (R) × (T) / P
= (10/3 mol) × (0.0821 L·atm/(mol·K)) × (273 K) / (1 atm)

Calculate the volume:
V = 6.322 L

Therefore, when 10 g of hydrogen is combined with nitrogen, approximately 6.322 liters of ammonia at STP are produced.