Question

What is the mass of 3.45l of gaseous ammonia (nh3) at stp? round to 3 significant figures.

Answer 1

To find the mass of gaseous ammonia (NH3) at STP, you can use the ideal gas law equation (PV = nRT). At STP, the pressure is 1 atm and the temperature is 273 K. Using the given volume of 3.45 L, you can calculate the number of moles of NH3 and then determine the mass by multiplying by the molar mass.

Step-by-step explanation:

To find the mass of gaseous ammonia (NH3) at STP, we need to 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 gas constant, and T is the temperature. At STP, the pressure is 1 atm and the temperature is 273 K. We can rearrange the equation to solve for n:

n = PV / RT

Given that 1 mole of a gas occupies a volume of 22.4 L at STP, we can calculate the number of moles of NH3 in 3.45 L:

n = (3.45 L) / (22.4 L/mol) = 0.15402 mol

Finally, we can calculate the mass of NH3 using its molar mass:

mass = n x molar mass = (0.15402 mol) x (17.03 g/mol) = 2.62 g

Answer 2

The mass of 3.45L of gaseous ammonia (NH3) at STP is approximately 4.47g when rounded to three significant figures.

Step-by-step explanation:

To find the mass of 3.45L of gaseous ammonia (NH3) at standard temperature and pressure (STP), we can use the molar volume of a gas at STP, which is 22.4L per mole. The molar mass of NH3 is 17g/mol. Using these values, we can calculate the mass of ammonia in 3.45L.

First, calculate the number of moles in 3.45L of NH3:
Number of moles = Volume / Molar volume at STP = 3.45L / 22.4L/mol

Next, find the mass of these moles:
Mass = Number of moles × Molar mass of NH3 = (3.45L / 22.4L/mol) × 17g/mol

Performing the calculation:

Mass = (3.45L / 22.4L/mol) × 17g/mol = 0.26295 moles × 17g/mol ≈ 4.47g

Therefore, the mass of 3.45L of NH3 at STP is approximately 4.47g, rounded to three significant figures.