Answer:
0.4 M
Explanation:
The process that takes place in an aqueous K₂HPO₄ solution is:
First we <u>calculate how many K₂HPO₄ moles are there in 200 mL of a 0.2 M solution</u>:
- 200 mL * 0.2 M = 40 mmol K₂HPO₄
Then we <u>convert K₂HPO₄ moles into K⁺ moles</u>, using the <em>stoichiometric coefficients</em> of the reaction above:
- 40 mmol K₂HPO₄ *
= 80 mmol K⁺
Finally we <em>divide the number of K⁺ moles by the volume</em>, to <u>calculate the molarity</u>:
- 80 mmol K⁺ / 200 mL = 0.4 M
Answer:
D) It has a different unit than atomic mass.
Answer:
The vapor pressure in solution is 0,0051 atm
Explanation:
This is the formula for vapor pressure lowering, the colligative property.
P vapor = Pressure sv pure . Xsv
Where Xsv is data.
Xsv means Molar fraction (moles solvent/total n° moles)
Vapor pressure of water, pure is 17.5 mmHg
P vapor = 0,0313 atm . 0163
P vapor in solution = 0,0051 atm
Molar fraction does not have units
A solution will have less vapor pressure than that observed in the pure solvent.
Answer:
The interaction reaction of calcium oxide and water leads to the formation of calcium hydroxide, this reaction is exothermic, which indicates that energy is released.
CaO(s) + H2O ⇒ Ca(OH)2
Explanation:
Calcium oxide reacts violently with water, causing it to reach 90 C. It then forms calcium hydroxide, also called slaked lime. It is heated because it releases energy in the form of heat, because the new substance formed (slaked lime) has less internal energy than the original and this is released in the form of heat. As a general rule, acid and base solutions are exothermic.