Answer:
150.1 mL
Explanation:
Step 1: Given data
- Density of benzene (ρ): 0.879 g/mL
- Mass of the sample of benzene (m): 131.9 g
- Volume of the sample of benzene (V): ?
Step 2: Calculate the volume of the sample of benzene
Density is an intrinsic property. It is equal to the quotient between the mass and the volume of the sample of benzene.
ρ = m/V
V = m/ρ
V = 131.9 g/(0.879 g/mL)
V = 150.1 mL
The answer to 4 is A.
The answer to 5 is C.
Answer:
49.86 × 10²³ atoms of Al
Explanation:
Given data:
Number of moles of Al = 8.28 mol
Number of atoms = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For 8.28 moles of Al:
1 mole = 6.022 × 10²³ atoms of Al
8.28 mol×6.022 × 10²³ atoms / 1mol
49.86 × 10²³ atoms of Al
Density = mass / volume
Mass = 5 kg
Volume = 50 cm³
d = 5 / 50
d = 0,1 kg/cm³
Lithium has 1 valence electron available for bonding. So its A.
