Answer:
f = 1.09 × 10¹⁵ Hz
Explanation:
Given data:
Frequency of wave = ?
Wavelength of wave = 2.73 ×10⁻⁷ m
Solution:
Formula:
Speed of light = frequency × wavelength
speed of light = 3× 10⁸ m/s
by putting values,
3× 10⁸ m/s = f × 2.73 ×10⁻⁷ m
f = 3× 10⁸ m/s / 2.73 ×10⁻⁷ m
f = 1.09 × 10¹⁵s⁻¹
s⁻¹ = Hz
f = 1.09 × 10¹⁵ Hz
It would take 8 antacid tablets to produce 120 mL of CO2 gas.
Answer:
Reduction
Explanation:
Reduction:
Reduction involve the gain of electron and oxidation number is decreased.
Mn⁺⁷ +3e⁻ → Mn⁴⁺
Mn gets three electrons , its oxidation state reduced from +7 to +4 so Mn gets reduced.
Examples:
Consider the following reactions.
4KI + 2CuCl₂ → 2CuI + I₂ + 4KCl
the oxidation state of copper is changed from +2 to +1 so copper get reduced.
CO + H₂O → CO₂ + H₂
the oxidation state of carbon is +2 on reactant side and on product side it becomes +4 so carbon get oxidized.
H₂S + 2NaOH → Na₂S + 2H₂O
The oxidation sate of sulfur is -2 on reactant side and in product side it is also -2 so it neither oxidized nor reduced.
n = m/M = 2/18 = 1/9 ~0,1 mol
<h3>
Answer:</h3>
Lead-205 (Pb-205)
<h3>
Explanation:</h3>
<u>We are given;</u>
We are supposed to identify its product after an alpha decay;
- Polonium-209 has a mass number of 209 and an atomic number of 84.
- When an element undergoes an alpha decay, the mass number decreases by 4 while the atomic number decreases by 2.
- Therefore, when Po-209 undergoes alpha decay it results to the formation of a product with a mass number of 205 and atomic number of 82.
- The product from this decay is Pb-205, because Pb-205 has a mass number of 205 and atomic number 82.
- The equation for the decay is;
²⁰⁹₈₄Po → ²⁰⁵₈₂Pb + ⁴₂He
- Note; An alpha particle is represented by a helium nucleus, ⁴₂He.
