Answer:
1.02 × 10⁶ g
Explanation:
Step 1: Given data
- Volume of the balloon (V): 5400 m³
- Absolute pressure (P): 1.10 × 10⁵ Pa
- Molar mass of He (M): 4.002 g/mol
Step 2: Convert "V" to L
We will use the conversion factor 1 m³ = 1000 L.
5400 m³ × 1000 L/1 m³ = 5.400 × 10⁶ L
Step 3: Convert "P" to atm
We will use the conversion factor 1 atm = 101325 Pa.
1.10 × 10⁵ Pa × 1 atm / 101325 Pa = 1.09 atm
Step 4: Calculate the moles of He (n)
We will use the ideal gas equation.
P × V = n × R × T
n = P × V / R × T
n = 1.09 atm × 5.400 × 10⁶ L / 0.08206 atm.L/mol.K × 280 K
n = 2.56 × 10⁵ mol
Step 5: Calculate the mass of He (m)
We will use the following expression.
m = n × M
m = 2.56 × 10⁵ mol × 4.002 g/mol
m = 1.02 × 10⁶ g
Answer:
150.0 mL.
Explanation:
- It is known that the no. of millimoles of HNO₃ before dilution = the no. of millimoles of HNO₃ after dilution.
∵ (MV) before dilution = (MV) after dilution.
<em>∴ V before dilution = (MV) after dilution / M before dilution</em> = (0.15 M)(500.0 mL)/(0.50 M) = <em>150.0 mL.</em>
<span>The molecular formula for phosphoric acid is H3PO4 and has 97.994 grams per mol. In a sample of 658 grams of phosphoric acid, there are 6.71 mols of phosphoric acid.</span>
