Answer:
An exact number is a value that is known with complete certainty. Like for Examples of exact numbers are counted numbers of objects or certain unit conversions. For example, there are exactly 3 feet in 1 yard. There are exactly 12 eggs in a dozen. A class may contain exactly 25 students.
Explanation:
Hope this helps.
Have a good night ma´am/sir.
Be safe!
Volume required for neutralization V will be:
V * 0.2125 M HCl = 25 mL * 0.17 M
V = 20 ml
First part:
When 10 mL is added we can apply Henderson equation to get the result, so:
The pH will be of basic buffer
pOH = pKb + log(salt/base)
or pOH = 4.19 + log (0.2125*10 / 25*0.17 - 10*0.2125 )
pOH = 4.19 and pH = 14 - 4.19 = 9.81
Second part:
When 20 ml is added, there is only salt formed
The pH will be salt of strong acid and weak base
So pH = 7 - 0.5 pKb - 0.5 log C
where C is the concentration of the salt formed so:
pH = 7 - (0.5*4.19) - (0.5 log (25*0.17) / (25+20))
= 5.42
Third part:
When 30 ml of the acid has been added,
The pH will be of the remaining strong acid
pH = - log (0.2125*10 / 25 + 30 )
= 1.326
Answer: concentration of solutions are expressed in various ways mol/L, mol/dm3, g/L etc
Explanation:
Answer:
Sry man wish I knew trust me tho you should go over it with your parents just let them know that your struggling and maybe they will go over it and help you get a better understanding of it also try asking an older sibling but yeah good luck with that have a good night!
Explanation:
Answer:
Nitrogen has 5 valence electrons
Explanation:
nitrogen has it's attoms form triple bonds which are very hard to break
so non-reactive