Answer:
you must add 50 mL
Explanation:
Hi
KOH is a strong base and by adding 100mL 0.05M you will have an amount of 5 millimol.
NaCN is a base and by adding 50 mL 0,150 M you will have an amount of 7,5 mmol.
HCl is a acid and by adding 200 mL 0,075 M you will have an amount of 15 mmol.
The acid reacts with the bases leaving 2.5 mmol unreacted.
Na3PO4 is a base and by adding 50 mL 0,1 M you will have an amount of 5 mmol.
The 2.5 mmol of acid react with the base PO4 ^ -3 forming a regulatory solution of PO4 ^ -3 and HPO4 ^ -2 of pKa 2.12
5 mmol of acid (HNO3) must be added to obtain a regulatory solution formed by the same amount of HPO4 ^ -2 (2.5 mmol) and H2PO4 ^ -1 (2.5 mmol) with pKa 7.21
Considering a quantity of 5 mmol of HNO3 of concentration 0.1 M, 50 mL must be added.
To calculate the pH of the regulatory solution you should consider pH = pKa × Ca / Cb pH = 7.21 × 2.5 / 2.5 = 7.21 Being in the same solution the volume is the same and can be simplified to achieve a faster calculation.
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Answer:
Explanation:
Molar mass is the mass of a given substance divided by the amount of that substance, measured in g/mol. For example, the atomic mass of titanium is 47.88 amu or 47.88 g/mol. In 47.88 grams of titanium, there is one mole, or 6.022 x 1023 titanium atoms.
Answer:
Spot (4) Has evidence that there were waves here at some point. It looks as if the sand/surface debris was moved back and forth, creating this pattern in the sand. Spots (5) and (7) show evidence of water erosion. The smooth edges of both hills mean that water once flowed through that area, carrying little pebbles and rocks that gradually shaped and smoothed those mounds. An example for this would be how there are smooth areas in the Grand Canyon where scientists have concluded that some, if not all, of the Grand Canyon was formed by flowing water. "Rapid uplift, cracking, and surface drainage of receding floodwaters provide both the path and the necessary volume of water to quickly carve out Grand Canyon," says scholars on icr.org.
Explanation:
Water Erosion exists.
The earwax is located in the ear canal. Earwax is important because it moisturizes the skin of ear, preventing dry itchy ears. It also contaisn special chemicals that fight of ear infections.
~Deceptiøn
Weight, the amount of force applied weight.
