<u>Answer:</u> The amount of sample left after 20 years is 288.522 g and after 50 years is 144.26 g
<u>Explanation:</u>
We are given a function that calculates the amount of sample remaining after 't' years, which is:

Putting values in above equation:


Hence, the amount of sample left after 20 years is 288.522 g
Putting values in above equation:


Hence, the amount of sample left after 50 years is 144.26 g
Answer:
626.7nm
Explanation:
The energy of a photon is defined as:
E = hc / λ
<em>Where E is the energy of the photon, h is Planck constant (6.626x10⁻³⁴Js), c is speed of light (3x10⁸m/s) and </em>λ is the wavelength of light
The energy of 1 photon is:
(191000 J / mol) ₓ (1 mole / 6.022x10²³) = 3.1717x10⁻¹⁹ J
Replacing:
3.1717x10⁻¹⁹ J = <em>6.626x10⁻³⁴Jsₓ3x10⁸m/s / </em>λ
λ = 6.267x10⁻⁷m
as 1nm = 1x10⁻⁹m:
6.267x10⁻⁷m ₓ (1nm / 1x10⁻⁹m) =
<h3>626.7nm</h3>
Answer:
Why do we all not know the answer to this on the practical
Explanation:
Rise, decrease, away from ocean, towards land
The correct answer is <span>Antoine-Laurent de Lavoisier. Hope this helps!</span>