Answer:
6.24%
Explanation:
Molality by definition means a measurement of the number of moles of solute in solution with 1000 gm or 1Kg solvent. Notice the difference that Molarity is defined on the volume of solution and Molality on the mass of solvent.
So, An aqueous solution of iron(II) iodide has a concentration of 0.215 molal.
means 0.215 moles are present in 1 Kg of solvent.
The molar mass of Fe2I = 309.65 g / mole
mass of FeI2 = moles x molar mass
= 0.215 x 309.65
=66.57 gm
mass % of FeI2 = mass of FeI2 x 100 / total mass
= 66.57x 100 / (1000 +66.57)
= 6.24%
Answer : 0.25 M
explanation :
- Molarity is the number of moles of solute per liters of solvent.
- Molarity (M) = (n) / V (liter) = 2 / 8 = 0.25 M
Answer:
400°C
Explanation:
22,000 cal / (0.11 cal/g°C x 500 g) = 400°C
Answer:
Modern whales evolved by natural selection over long time periods through descent from common ancestors
Explanation:
According to the evolutionary theory proposed by Darwin, natural selection is a biological process by which organisms adapt and change in response to their environment. In this case, ancient whales that were better suited to environmental conditions survived and produced more offspring than non-adapted individuals. In consequence, predominant adaptive traits observed in modern whales were favored by natural selection in the past, while unsuccessful phenotypes progressively disappeared.
