Answer:
a. 5.36x10⁻⁴ g/mL
b. 4.29x10⁻⁵ g/mL
Explanation:
As the units for concentration are not specified, I'll respond using g/mL.
a. We <em>divide the sample mass by the final volume</em> in order to <u>calculate the concentration</u>:
- 0.268 g / 500 mL = 5.36x10⁻⁴ g/mL
b. We can use C₁V₁=C₂V₂ for this question:
- 8.00 mL * 5.36x10⁻⁴ g/mL = C₂ * 100.00 mL
Answer:
0.18× 10²³ molecules
Explanation:
Given data:
Mass of copper hydroxide = 3.30 g
Number of molecules = ?
Solution:
Number of moles = mass/molar mass
Number of moles = 3.30 g/97.56 g/mol
Number of moles = 0.03 mol
Avogadro number:
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.
1 mole = 6.022 × 10²³ molecules
0.03 mol × 6.022 × 10²³ molecules / 1mol
0.18× 10²³ molecules
Ideal gas law:
PV=nRT ⇒ V=nRT / P
P=pressure=1 atm
V=volume
n=number moles=2.10 moles
R=0,082 Atm l/ºK mol
T=temperature=273 K
V=(2.10 moles*0.082 (atm l)/º(K mol)*237ºK) / 1 atm=47.01 litres
47.1 L
