Answer:
[HF]₀ = 0.125M
Explanation:
NaOH + HF => NaF + H₂O
Adding 20ml of 0.200M NaOH into 25ml of HF solution neutralizes 0.004 mole of HF leaving 0.004 mole NaF in 0.045L with 0.001M H⁺ at pH = 3. This is 0.089M NaF and 0.001M HF remaining.
=> 45ml of solution with pH = 3 and contains 0.089M NaF from titration becomes a common ion problem.
HF ⇄ H⁺ + F⁻
C(eq) [HF] 10⁻³M 0.089M (<= soln after adding 20ml 0.200M NaOH)
Ka = [H⁺][F⁻]/[HF]₀ => [HF]₀ = [H⁺][F⁻]/Ka
[HF]₀ = (0.001)(0.089)/(7.1 x 10⁻⁴) M = 0.125M
Answer:
The correct answer is - option D. photosynthesis.
Explanation:
It is shown by the study that most of the atmospheric oxygen comes from the photosynthesis by plants as oxygen is the byproduct of the photosynthesis. Photosynthesis is the process that uses light energy, carbon dioxide, and water to produce food or glucose/sugar and release oxygen as the byproduct.
Many scientists believe that oceanic phytoplankton that releases oxygen by the photosynthesis process makes 80 to 85% of the total oxygen of the atmospheric oxygen.
Answer:
Sorry pal! Didn't understand your language.
:(
Explanation:
Explanation:
c. h. o
66.7%. 11.1%. 22.2%
____. ____. ____
12. 1. 16
1.558. 11.1. 1.39. (divide by the smallest)
1. 8. 1
empirical formula=ch8o
Data:
V1 = 6.7 liter
T1 = 23° = 23 + 273.15 K = 300.15 K
P1 = 0.98 atm
V2 = 2.7 liter
T2 = 125° = 125 + 273.15 K = 398.15 K
P2 = ?
Formula:
Combined law of ideal gases: P1 V1 / T1 = P2 V2 / T2
=> P2 = P1 V1 T2 / (T1 V2)
P2 = 0.98 atm * 6.7 liter * 398.15 K / (300.15K * 2.7 liter)
P2 = 3.22 atm