Data:
V (volume) = 500.0 mL = 0.5 L
T (temperature) = 15.00ºC
(converting in Kelvin) → TK = TC + 273 → TK = 15 + 273 = 288 K
P (pressure) = 736.0 mmHg
R (constant) = 62.363 (mmHg*L/mol*K)
m (mass) = 2.688 g
M (Molar Mass) = ? (g/mol)
Formula: General Gas Equation
Solving:
Product of extremes equals product of means:
Therefore: <span>The gas found to have such a molar mass is
xenon gas</span>
Answer: The number of moles in 250.0 L of He at STP is 11.0 mole.
Explanation:
- It is known that 1.0 mole of a gas at STP conditions will occupy 22.7 L.
- To show this information: STP means that T = 0.0 °C = 273.15 K and P = 1.0 kPa = (100/101.325) = 0.9869 atm.
- From the ideal gas law: PV = nRT.
- Where, P is the pressure in atm <em>(P = 1.0 atm at STP).</em>
- n is the number of moles (n = 1.0 mole).
- R is the general gas constant (R = 0.0821 L.atm/mol.K).
- T is the temperature in K (T = 273.15 K at STP).
- and now we can get the volume of 1.0 mole at STP: V = nRT/P
- V = (1.0 mole x 0.0821 L.atm/mol.K x 273.15 K) / (0.9869 atm) = 22.7 L.
- Now, we can get the number of moles of 250.0 L of He at STP:
<em>Using cross multiplication:</em>
1.0 mole → 22.7 L
??? mole → 250.0 L
- The number of moles in 250.0 L of He at STP = (250.0 L x 1.0 mole) / (22.7 L) = 11.01 mole ≅ 11.0 mole.
Answer:
0.5968 g/mL
Explanation:
To calculate density:
density
Therefore,12.52g divide by 20.98mL is 0.5968g/mL