Answer:
34.15% is the mass percentage of calcium in the limestone.
Explanation:
Mass of precipitate that is calcium oxalate = 140.2 mg = 0.1402 g
1 mg = 0.001 g
Moles of calcium oxalate = 
1 mole of calcium oxalate have 1 mole of calcium atom.
Then 0.001095 moles of calcium oxalate will have 0.001095 moles of calcium atom.
Mass of 0.001095 moles of calcium :
0.001095 mol × 40 g/mol = 0.04381 g
Mass of sample of limestone = 128.3 mg = 0.1283 g
Percentage of calcium in limestone:
34.15% is the mass percentage of calcium in the limestone.
Answer:
Mixtures can be either homogeneous or heterogeneous. A mixture in which its constituents are distributed uniformly is called homogeneous mixture, such as salt in water. A mixture in which its constituents are not distributed uniformly is called heterogeneous mixture, such as sand in water.
Explanation:
Answer:
1.9 L
Explanation:
Step 1: Given data
- Initial number of moles of air (n₁): 4.0 mol
- Initial volume of the balloon (V₁): 2.5 L
- Final number of moles of air (n₂): 3.0 mol
- Final volume of the balloon (V₂): ?
Step 2: Calculate the final volume of the balloon
According to Avogadro's law, the volume of an ideal gas is directly proportional to the number of moles. We can calculate the final volume of the balloon using the following expression.
V₁ / n₁ = V₂ / n₂
V₂ = V₁ × n₂ / n₁
V₂ = 2.5 L × 3.0 mol / 4.0 mol
V₂ = 1.9 L
When particles collide with the surface of the solid.
