Mole fraction of oxygen gas: 0.381
Additional clarification
Given:
2.31 atm Oxygen
3.75 atm Hydrogen
Required:
Mole fraction of Oxygen
Calculation:
According to Dalton’s Law of partial pressures
P tot = P₁ + P₂ +.. + Pₙ
Substituting values:
P tot = P O₂ + P H₂
P tot = 2.31 atm + 3.75 atm
P tot = 6.06 atm
Mole fraction of O₂ (X O₂):
P O₂ = X O₂ x P tot
X O₂ = P O₂ / P tot
X O₂ = 2.31 / 6.06
X O₂ = 0.381
Responses: a. 1.28 mol/L; b. 17.0 %; c. 0.0227; d. 1.29 mol/kg Explanation: a. Molar concentration: c = moles/litres. Moles = 167 × 1/159.61. After performing the calculation, Moles = 1.046 mol. Litres = 820 × 1/1000. Hence, Litres = 0.8200 L. Calculating the molar concentration gives c = 1.046/0.8200, resulting in c = 1.28 mol·L⁻¹. b. Percent by mass: Mass % = mass of solute / mass of solution × 100 %. Mass of solution = volume × density, therefore, Mass of solution = 820 × 1.195. By calculating this, Mass of solution = 979.9 g. Thus, Mass % = 167/979.9 × 100, which results in Mass % = 17.0 %. c. Mole fraction: χ = moles of solute / (moles of solvent + moles of solute). Mass of solvent = mass of solution – mass of solute; namely, Mass of solvent = 979.9 – 167. Converting this to moles gives Moles of water = 812.9 × 1/18.02, which results in Moles of water = 45.11 mol. The total moles are 1.046 + 45.11, leading to Total moles = 46.16 mol. Finally, the mole fraction is calculated as χ = 1.046/46.16, equating to χ = 0.0227. d. Molal concentration: b = moles of solute / kilograms of solvent. Mass of solvent = 812.9 g = 0.8129 kg. Therefore, the molal concentration yields: b = 1.046/0.8129 = 1.29 mol/kg.
Answer:
The specific heat value for silver is 0.236 J/g-C.
Explanation:
Silver has a mass of 25 grams.
The temperature shifts from 31.5° C to 58.7° C.
The required heat is equivalent to 25 g.
To determine silver's specific heat, the following equation applies:
Where c represents the specific heat of silver.
Thus, the specific heat of silver is 0.236 J/g-C.
Response:
a. To purify a gypsum sample, you will need the following equipment: Bunsen burner, beaker, filter funnel, stirring rod, and filter paper.
b. Gypsum, a sulfate mineral consisting of calcium sulfate dihydrate, can be purified by following these steps:
1. Add water to the gypsum in a beaker.
2. Stir the mixture thoroughly with the stirring rod.
3. Use the filter paper and filter funnel to remove excess solids from the mixture.
4. Heat the filtered mixture on the Bunsen burner to evaporate the remaining water.
5. After cooling, filter again through the filter paper to obtain pure gypsum.
