Answer:
b) By mixing weak base with its conjugate acid and then adjusting the pH with strong acid.
Explanation:
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In this case, considering that the buffer required a pH greater than 7 where the basic conditions are present, we need a weak base and its conjugate base in order to assure such pH greater than 7. Moreover, by using a strong acid, we can gently add it in order to decrease the pH up to 7.4 via a properly measured neutralization of the necessary moles of base up to a hydrogen concentration of 3.98x10⁻⁸ (pH). Therefore, answer is b) By mixing weak base with its conjugate acid and then adjusting the pH with strong acid.
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In most cases, the two major climatic factors affecting the distribution of organisms in terrestrial ecosystems are the amount of water and temperatures. Terrestrial ecosystems rely on the sun's energy to support the growth and metabolism of the organisms. Plants use the sunlight, then they supply the organisms that are higher up the food chain with energy and the structural buildings blocks of life. Water is also essential for the survival of these organisms.
C. Duh. No one has to agree with a successful thesis.
Answer:
Explanation:
Using Ohm's law
V ( voltage) = I (current A) × Resistance R in ohms
R = 7.0 × 10⁹Ω
V = 80 mV = 80 / 1000 = 0.08 V
0.08 V = I × 7.0 × 10⁹Ω
a) I = 0.08 V / 7.0 × 10⁹Ω = 1.142857 × 10 ⁻¹¹ A
b) quantity of charge = I × t = 1.142857 × 10 ⁻¹¹ A × 0.85 s = 9.7142857 × 10⁻¹² C
number of Na⁺ ions ( q = +e) = 9.7142857 × 10⁻¹² C / 1.6 × 10⁻¹⁹ C = 60714285.714 Na⁺ ions
1.Frost Wedging (Freeze-Thaw)
Water expands by 9 percent when it freezes. As it expands, it exerts up to 4.3 million pounds per square foot of pressure. Since water seeks low points, repeated freezing and thawing can lead to deep vertical fissures as cracks are extended downward. Cracks that allow entry of roots lead to similar wedging.
2.Crystal Formation
Crystal formation cracks rock in a similar way. Most water contains dissolved salts. When water in rock fissures evaporate, the salt concentration increases, which leads to crystallization. This occurs in arid regions where the humidity fluctuates widely, so that the salt can be redissolved and carried into new fissures.
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