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.
successes with your homework
Air is heterogenous mixture because it is made of components that can seperate, The process to sperate air into its components is called fractional distillation. In this process, air coverts to a liquid form, and then it seprates into seperate layers, which then helps you to see air's components.
hopefully this helps you.
Potassium reacts with bromine to produce Potassium Bromide, because bromine has a (-) charge while potassium has a (+) charge. Bromine needs to gain one more electron to have a noble gas configuration or 8 valence electrons, & potassium needs to lose one so they make a transference of electrons in an ionic bond.
0.598 m
598 mm × (1 m/1000 mm) = 0.598 m
Answer:
Creo que es D pero no tan segura
Explanation: