The concentration (M) of HCl in a solution prepared by dissolving 5.5 g of HCl in 200 g of (C2H6O) is __________ M. The density of the solution is 0.79 g/mL. Here are some possible answers.
a. 21
b. 0.93
c. 0.58
d. 1.72
e. 6.0 × 10-4
2007-10-19 06:29:19 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
Molarity (M) is defined as moles of solute per liter of solution. So, first convert the mass of ethanol into a volume using the density. (200 g/0.79 g/mL) Convert that to liters by dividing by 1000.
Next convert the mass of HCl into moles by dividing by the molar mass of HCl.
FInally, divide the moles of HCl by the volume of ethanol (in L) and you've got the molarity of the solution.
I like the other answer better than mine....:(
2007-10-19 06:35:19 · answer #1 · answered by hcbiochem 7 · 0⤊ 0⤋
The answer is C) 0.58 M.
5.5g of HCl contains 0.15 moles
Calculating the volume of solvent using the mass and the density gives 253 mL
SO 0.15 moles are in 253 mL so there will be 0.58 in 1000mL
2007-10-19 06:39:14 · answer #2 · answered by haile d 3 · 3⤊ 0⤋
Volume of Solution = (5.5 + 200)/0.79 = 260 mL = 0.26 L
Moles HCl = 5.5 g / 36.54 g/mole = 0.15 moles
M = moles / liter = 0.15 /0.26 = 0.58
C is the answer
2007-10-19 06:35:30 · answer #3 · answered by ferrous lad 4 · 2⤊ 0⤋
C(M)=number of moles/solution volume
C(M)=(5.5/36.5)/(200/0.79)=6.0x10^-4
/// C(M)= #moles/ mass/density
2007-10-19 06:39:45 · answer #4 · answered by Radu 2 · 0⤊ 0⤋