C₀=2 mol/l
c₁=0.400 mol/l
v₁=100.0 ml = 0.1 l
c₁v₁=c₀v₀
v₀=c₁v₁/c₀
v(H₂O)=v₁-v₀
v₀=0.1*0.400/2=0.02 l = 20 ml
v(H₂O)=100 - 20 = 80 ml
It is necessary to mix 20 ml of the feed solution and 80 ml of water.
72g
Explanation:
Given parameters:
Number of moles of LiOH = 3moles
Unknown:
Mass of LiOH = ?
Solution:
A mole of substance is a unit used to make quantitative measures in chemistry.
It is the amount of substance that contains the avogadro's number of particles.
The mole is related to mass using the expression below;
Mass of a substance = number of moles x molar mass
Molar mass of LiOH = 7 + 16 + 1 = 24g/mol
Mass of LiOH = 3 x 24 = 72g
learn more:
Number of moles brainly.com/question/1841136
#learnwithBrainly
Mole fraction is a unit of concentration, defined to be equal to the number of moles of a component divided by the total number of moles of a solution. Because it is a ratio, mole fraction is a unitless expression. The mole fraction of all components of a solution, when added together, will equal 1.
Answer:
Explanation
Comment
Normally you would just use m*c*delta T. But the c is the same in both cases, so you need just use m*deltaT
Givens
25 degrees
m = ?
T = 25
t = final temp = 75
93 degrees
m = 250
T = 93
t = final temp = 75
Solution
(t - 25)*m = (93 - t) * 250 Remove the brackets
75*m - 25m = 93*250 - 250*75 Combine the right
m(75 - 25) = 23250 - 250*75
50 m = 23250 - 18750 Combine
50 m = 4500 Divide both sides by 50
50*m/50 = 4500/50
m = 90
Answer: 90 grams are needed.
