Answer:
Mass = 141.6 g
Explanation:
Given data:
Mass of Kr in gram = ?
Volume in L = 9.59 L
Temperature = 46.0°C
Pressure = 4.62 atm
Solution:
The given problem will be solve by using general gas equation,
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K
T = temperature in kelvin
Now we will convert the temperature.
46.0+273 = 319 K
4.62 atm × 9.59 L = n× 0.0821 atm.L/ mol.K ×319 K
44.3 atm.L = n×26.19 atm.L/ mol
n = 44.3 atm.L / 26.19 atm.L/ mol
n = 1.69 mol
Mass in gram:
Mass = number of moles × molar mass
Mass = 1.69 mol × 83.79 g/mol
Mass = 141.6 g
Answer:
91.2 nm
Explanation:
The Rydberg equation is given by the formula
1/ λ = Rh ( 1/ n₁² - 1/ n₂²)
where
λ is the wavelength
Rh is Rydberg constant
and n₁ and n₂ are the energy levels of the transion.
We can see from this equation that the wavelength is inversely proportional to the difference of the squares of the inverse of the quantum numbers n₁ and n₂. It follows then that the smallest wavelength will be given when the the transitions are between the greatest separation between n₁ and n₂ whicg occurs when n1= 1 and n₂= ∞ , that is the greater the separation in energy levels the shorter the wavelength.
Substituting for n₁ and n₂ and solving for λ :
1/λ = 1.0974 x 10⁷ m⁻¹ x ( 1/1² -1/ ∞²) = 1.0974 x 10⁷ m⁻¹ x ( 1/1² - 0) =
λ = 1/1.0974 x 10⁷ m = 9.1 x 10⁻8 m = 91.2 nm
<span>A chemical change has occurred creating a precipitate.
Just had that question on a quiz. XP
Hope I helped :)</span>
We generally represent an element by its symbol. provided with the atomic number and mass number or atomic mass
Atomic number is the number of protons present in an element. It is constant for an element.
The mass number of element is the sum of number of protons and number of neutrons
The atomic mass is the total mass of all the protons and neutrons present in the element (in its nucleus).
the number of electrons is equal to number of protons in a neutral atom of element.
The mass of electrons is not included in the total atomic mass of element as it is very low.
So here
12 = it is the number of protons = atomic number of element.
The true statements are
The combined mass of protons and neutrons is 24.305