To calculate this,
We know that energy is 1 photon
E = hc/wavelenth
wavelength of 10.0 m
Solution:
h = 6.626 x 10^-34 Jsec
C = 2.9979 x 10^8 m/sec
E = 6.626 10^-34 * 2.9979 10^8 / 10 = 1.9864 10^-26J
Then, the number of photons is computed by:
n = 1000 / 1.9864 10^-26 = 5.04 10^28 photons
I think that the answer is B, but I may be wrong...
Answer:
The particles in a solid are tightly packed and locked in place. ... The particles in a liquid are close together (touching) but they are able to move/slide/flow past each other. The particles in a gas are fast moving and are able to spread apart from each other.
Explanation:
1) Left up: a chemical change. We can see new substance (red-blue) is formed from one blue and one red atom.
In chemical change new substances are formed, the atoms are rearranged and the reaction is followed by an energy change.
2) Left down: a chemical change. We can see new substance (red-blue) is formed from two blue and one red atoms.
3) MIddle: a physical change. There is no new substance. Bonds are not broken.
4) Right up: a chemical change. Bonds are broken.
5) Right down: a physical change. Change of state of matter.
Answer:
1.41 × 10⁻¹⁰ M
Explanation:
We have a solution with a pH of 9.85 at 25 °C. We can calculate the concentration of H⁺ using the following expression.
pH = -log [H⁺]
[H⁺] = antilog -pH
[H⁺] = antilog -9.85
[H⁺] = 1.41 × 10⁻¹⁰ M
H⁺ is usually associated with water molecules forming hydronium ions.
H⁺ + H₂O → H₃O⁺
Then, the concentration of H₃O⁺ ions is 1.41 × 10⁻¹⁰ M.
