A substance weighing 572 g contains 107.6 10 ^ 23 molecules and a density of 1.43 kg / m ^ 3.

| September 14, 2021 | education

A substance weighing 572 g contains 107.6 10 ^ 23 molecules and a density of 1.43 kg / m ^ 3. Find the volume (V, L) and the concentration of the substance (n, 10 ^ 20 cm ^ -3). Calculate the mass of one molecule of a given substance.

m = 572 g = 0.572 kg.
N = 107.6 * 10 ^ 23.
ρ = 1.43 kg / m ^ 3.
V -?
n -?
m1 -?
According to the definition, the density of a substance ρ is the mass of a substance taken in a unit of its volume: ρ = m / V.
V = m / ρ.
V = 0.572 kg / 1.43 kg / m ^ 3 = 0.4 m ^ 3.
1 m ^ 3 = 1000 l, 0.4 m ^ 3 = 400 l.
The concentration of molecules n is the ratio of the number of molecules N to the volume V occupied by these molecules.
n = N / V.
We convert the volume V = 0.4 m ^ 3 into cm ^ 3, knowing that 1 m ^ 3 = 1,000,000 cm ^ 3.
V = 0.4 m ^ 3 = 400,000 cm ^ 3.
n = 107.6 * 10 ^ 23/400000 cm ^ 3 = 0.269 * 10 ^ 20 cm ^ -3.
m1 = m / N.
m1 = 0.572 kg / 107.6 * 10 ^ 23 = 5.3 * 10 ^ -26 kg.
Answer: V = 400 l, n = 0.269 * 10 ^ 20 cm ^ -3, m1 = 5.3 * 10 ^ -26 kg.



One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.