I think you add 29.57 + 80 and the answer would be 30.37
Answer:
Landslides, Volcanoes, Earthquakes, and Floods. A opening in the Earth's surface through which melted rock, gases, and ash escape. Events in which molten rock spews out from the mantle to the surface of Earth as ash, lava, and gases
Explanation:
The contribution to the nature of light-
Thomas Young - wave nature of light (double-slit experiment)
Max Planck - E = hv
Albert Einstein - a quantum theory of light
Thomas Young proposed the most important double-slit experiment which shows that light acts like a wave and shows the pattern of interferences.
Max Planck proposed that light is proportional to frequency. He gave the equation, E = hv, where E is the energy of light, h is Planck's constant, and v is the frequency.
Albert Einstein proposed the quantum theory of light. He determined that light exists in discrete quanta of energy called photons.
To learn more about the nature of light, visit: brainly.com/question/4423091
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Answer:
I think it's answer is P4O6
I hope it's helpful for you...
Answer:
Explanation:
The usefulness of a buffer is its ability to resist changes in pH when small quantities of base or acid are added to it. This ability is the consequence of having both the conjugate base and the weak acid present in solution which will consume the added base or acid.
This capacity is lost if the ratio of the concentration of conjugate base to the concentration of weak acid differ by an order of magnitude. Since buffers having ratios differing by more will have their pH driven by either the weak acid or its conjugate base .
From the Henderson-Hasselbach equation we have that
pH = pKa + log [A⁻]/[HA]
thus
0.1 ≤ [A⁻]/[HA] ≤ 10
Therefore the log of this range is -1 to 1, and the pH will have a useful range of within +/- 1 the pKa of the buffer.
Now we are equipped to answer our question:
pH range = 3.9 +/- 1 = 2.9 through 4.9
