The idea here is that you need to figure out how many moles of magnesium chloride,
MgCl
2
, you need to have in the target solution, then use this value to determine what volume of the stock solution would contain this many moles.
As you know, molarity is defined as the number of moles of solute, which in your case is magnesium chloride, divided by liters of solution.
c
=
n
V
So, how many moles of magnesium chloride must be present in the target solution?
c
=
n
V
⇒
n
=
c
⋅
V
n
=
0.158 M
⋅
250.0
⋅
10
−
3
L
=
0.0395 moles MgCl
2
Now determine what volume of the target solution would contain this many moles of magnesium chloride
c
=
n
V
⇒
V
=
n
c
V
=
0.0395
moles
3.15
moles
L
=
0.01254 L
Rounded to three sig figs and expressed in mililiters, the volume will be
V
=
12.5 mL
So, to prepare your target solution, use a
12.5-mL
sample of the stock solution and add enough water to make the volume of the total solution equal to
250.0 mL
.
This is equivalent to diluting the
12.5-mL
sample of the stock solution by a dilution factor of
20
.
Answer:
Explanation:
Well, obviously a molecule with polar bonds can be polar in itself. It's like saying I am an atheltic person who can just reach the basketball rim with my head and also I can dunk.
But if the question is how can a molecule that in non-polar have polar bonds, well, its because the polar bonds' dipole cancels each other out. It's like a tight rope. If a person pulls in one direction, it intuitively, the rope would go in that direction. However, if a person pulls in the other direction with the same amount of force, the rope stays still. This is the same case. Although molecules can have different electronegativities, the pull of electrons in one direction is cancelled out by a pull in the opposite direction, making the net dipole 0.
This is common for main VSERP shaped molecules like linear, trigonal planar, tetrahedral, trigonal bipyramidal, and octahedral.
Answer:
The correct answer is B)About 5 percent
Explanation:
The approximate total size of the human nuclear genome is 3,200,000,000 base pairs. 1 to 1, 4% encode proteins, 24% are non-coding regions and the rest correspond to intergenic regions.
Answer:
N₂ + 3H₂ → 2NH₃
Explanation:
Chemical equation:
N₂ + H₂ → NH₃
Balanced chemical equation:
N₂ + 3H₂ → 2NH₃
Step 1:
N₂ + H₂ → NH₃
left hand side: Right hand side
N = 2 N = 1
H = 2 H = 3
Step 2:
N₂ + 3H₂ → NH₃
left hand side: Right hand side
N = 2 N = 1
H = 6 H = 3
Step 3:
N₂ + 3H₂ → 2NH₃
left hand side: Right hand side
N = 2 N = 2
H = 6 H = 6
