Well one mole of stuff, any stuff, including carbon dioxide, specifies
6.022
×
10
23
individual items of that stuff.
Explanation:
And thus we work out the quotient:
7.2
×
10
25
⋅
carbon dioxide molecules
6.022
×
10
23
⋅
carbon dioxide molecules
⋅
m
o
l
−
1
≅
120
⋅
m
o
l
carbon dioxide
.
This is dimensionally consistent, because we get an answer with units
1
m
o
l
−
1
=
1
1
mol
=
m
o
l
as required.
Answer:
pH = 2
A 0.010 M solution of hydrochloric acid, HCl, has a molarity of 0.010 M. This means that [H+] = 1 x 10-2 M. The pH of this aqueous solution of H+ ions is pH = 2
hope this helps :3
<span>1.16 moles/liter
The equation for freezing point depression in an ideal solution is
ΔTF = KF * b * i
where
ΔTF = depression in freezing point, defined as TF (pure) ⒠TF (solution). So in this case ΔTF = 2.15
KF = cryoscopic constant of the solvent (given as 1.86 âc/m)
b = molality of solute
i = van 't Hoff factor (number of ions of solute produced per molecule of solute). For glucose, that will be 1.
Solving for b, we get
ΔTF = KF * b * i
ΔTF/KF = b * i
ΔTF/(KF*i) = b
And substuting known values.
ΔTF/(KF*i) = b
2.15âc/(1.86âc/m * 1) = b
2.15/(1.86 1/m) = b
1.155913978 m = b
So the molarity of the solution is 1.16 moles/liter to 3 significant figures.</span>
The correct answer is:
b: Heluim
Explanation:
The caffeine contains:
carbon , nitrogen , oxygen ,
hydrogen.
Caffeine is a primary nervous system energizer of the methylxanthine class. It is the world's most universally consumed psychoactive drug. Unlike many other psychoactive elements, it is fair and unlimited in nearly all parts of the world. Caffeine can be arranged as an alkaloid, a term used for substances originated as end results of nitrogen metabolism in some plants.
Answer:
8.5155g NH3
Explanation:
the molar mass of NH3 is 17.031 g/mol
0.5 mol NH3 x 17.031 gNH3/1 mol NH3 = 8.5155g NH3
