Answer:
E = 19.89×10⁻¹⁶ J
λ = 1×10⁻¹ nm
Explanation:
Given data:
Frequency of xray = 3×10¹⁸ Hz
Wavelength of xray = ?
Energy of xray = ?
Solution:
speed of wave = wavelength × frequency
speed = 3×10⁸ m/s
3×10⁸ m/s = λ ×3×10¹⁸ s⁻¹
λ = 3×10⁸ m/s / 3×10¹⁸ s⁻¹
λ = 1×10⁻¹⁰m
m to nm:
λ = 1×10⁻¹⁰m×10⁹
λ = 1×10⁻¹ nm
Energy of x-ray:
E = h.f
h = plancks constant = 6.63×10⁻³⁴ Js
by putting values,
E = 6.63×10⁻³⁴ Js ×3×10¹⁸ s⁻
¹
E = 19.89×10⁻¹⁶ J
Answer:
0
Explanation:
Given parameters:
Half-life = 8.08days
Unknown:
What fraction is left unchanged after 16.16days = ?
Solution:
The half - life of a substance is the time taken for the half of a radioactive material to decay to half.
Day 0 Day 8.08 Day 16.16
100% 50% 0% Parent
0% 50% 100% Daughter
After 16.16 days, non of the original sample will remain unchanged.
Answer:
10.8amu
Explanation:
Given parameters:
Abundance of B - 10 = 20% = 0.2
Abundance of B - 11 = 80% = 0.8
Unknown:
Atomic mass of Boron = ?
Solution:
The atomic mass of Boron can be can be calculated using the expression below;
Atomic mass = (abundance of B - 10 x mass of isotope B - 10 ) +( abundance of B - 11 x mass of isotope B- 11)
Atomic mass = (0.2 x 10) + (0.8 x 11) = 2 + 8.8 = 10.8amu
Answer:
B. It tells whether products or reactants are favored at equilibrium.
