We know that the number of moles HCl in 14.3mL of 0.1M HCl can be found by multiplying the volume (in L) by the concentration (in M).
(0.0143L HCl)x(0.1M HCl)=0.00143 moles HCl
Since HCl reacts with KOH in a one to one molar ratio (KOH+HCl⇒H₂O+KCl), the number of moles HCl used to neutralize KOH is the number of moles KOH. Therefore the 25mL solution had to contain 0.00143mol KOH.
To find the mass of KOH in the original mixture you have to divide the number of moles of KOH by the 0.025L to find the molarity of the KOH solution..
(0.00143mol KOH)/(0.025L)=0.0572M KOH
Since the morality does not change when you take some of the solution away, we know that the 250mL solution also had a molarity of 0.0572. That being said you can find the number of moles the mixture had by multiplying 0.0572M KOH by 0.250L to get the number of moles of KOH.
(0.0572M KOH)x(0.250L)=0.0143mol KOH
Now you can find the mass of the KOH by multiplying it by its molar mass of 56.1g/mol.
0.0143molx56.1g/mol=0.802g KOH
Finally you can calulate the percent KOH of the original mixture by dividing the mass of the KOH by 5g.
0.802g/5g=0.1604
the original mixture was 16% KOH
I hope this helps.
There are 32 valence electrons for the Lewis structure for ClO4
Answer:
Water uses adhesive forces that allow it to stick to certain surfaces such as glass.
Explanation:
When the angle between vertical direction and the glass wall is small, surface tension is stronger and the component of gravity perpendicular to the glass wall is small. The result of this causes water to stick to the side of a glass.
Hope this helps!
Answer:
Hygroscopic
Explanation:
An hygroscopic substance is one that absorbs moisture from the atmosphere and becomes wet. Their ability to remove water from air is less than that of deliquescent substances. Most of the solid hygroscopic substances forms pasty substances and not solutions like the deliquescent compounds.
Examples are sodium trioxonitrate(v), copper(ii) oxide e.t.c
Efflorescence compounds gives off their water of crystallization to the atmosphere.
Answer : It is only one of those ancient sights which still exist and gives ancient antiquity to the great pyramid in Egypt. It is believed that the pyramids are the definition of prayers that still remains in the heart of the local people.
It is also one of seven wonders of the world that is under world heritage. Pyramids where only found in Egypt and nowhere else.
