Answer:
234.35 °C
Explanation:
Given data:
Volume of balloon = 125000 mL
Moles of oxygen = 3 mol
Pressure = 1 atm
Temperature = ?
Solution:
Formula:
PV = nRT
P = Pressure
V = volume
n = number of moles
R = ideal gas constant
T = temperature
Volume of balloon = 125000 mL × 1 L /1000 mL
Volume of balloon = 125 L
Now we will put the values:
Ideal gas constant = R = 0.0821 atm.L/mol.K
PV = nRT
T = PV/nR
T = 1 atm × 125 L/ 0.0821 atm.L/mol.K × 3 mol
T= 125 /0.2463 /K
T = 507.5 K
K to °C
507.5 K - 273.15 = 234.35 °C
Answer:
Mass = 4.5 g
Explanation:
Given data:
Number of atoms of iron = 4.85 ×10²² atoms
Mass of iron = ?
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,
4.85 × 10²² atoms of iron / 6.022 × 10²³ atoms × 1 mol
0.081 mol
Mass of iron:
Mass = number of moles × molar mass
Mass = 0.081 mol × 55.85 g/mol
Mass = 4.5 g
Answer:
A. The accepted model of the atom was changed.
Explanation:
Thomson described an atom that has the protons uniformly distributed within a circular atom with the electrons embedded . However, it cannot explain the emission of electrons from the surfaces of metals like photoelectric emission. it does not explain how the particle of the atom contribute significantly to the entire mass of an atom