Answer:
avogadro's constant
Explanation:
this is the fixed number of the atoms in the molecule of an element
avogadro's law states that equal volumes of gases<em> </em><em>at</em><em> </em><em>the</em><em> </em><em>same</em><em> </em><em>temperature</em><em> </em><em>and</em><em> </em><em>pressure</em><em> </em><em> </em><em>contain</em><em> </em><em>equal</em><em> </em><em>numbers</em><em> </em><em>of</em><em> </em><em>molecules</em><em> </em>
<em>that</em><em> </em><em>is</em><em> </em><em>all</em><em> </em><em>gases</em><em> </em><em>with</em><em> </em><em>same</em><em> </em><em>temperature</em><em> </em><em>and</em><em> </em><em>pressure</em><em> </em><em>will</em><em> </em><em>always</em><em> </em><em>have</em><em> </em><em>equal</em><em> </em><em>numbers</em><em> </em><em>of</em><em> </em><em>molecules</em><em> </em>
the molecular formula is calculated as follows
find the mole of each molecule
that is for carbon = 26.7/12= 2.23 moles
hydrogen= 2.24/1=2.24 moles
oxygen= 71.1/16=4.44 moles
find the mole ratio of each element
that is divide all moles by the smallest mole( 2.23)
for carbon=2.23/2.23=1,
hydrogen = 2.24/2,23=1
oxygen= 4.44/2.23= 2
the empirical formula = CHO2
therefore the molecular formula=(CHO2)n=270.1
{ ( 12x 1) + 1x1) +(16x2)}n=270.1
45n=270.1
n=6
molecular formula is therefore=(CHO2)6=C6H6O12
Answer:
M1 = 49.04 g/mol
Explanation:
The pure benzonitrile has freezing point -12.8°C. By adding a nonvolatile compound, the freezing point will be changed, a process called cryoscopy. The freezing point will be reduced. In this case, the new freezing point is -13.4°C. The variation at the temperature can be calculated by the equation:
ΔT = Kc*W*i
Where ΔT is the variation at the freezing temperature (without the solute less with the solute), Kc is the cryoscopy constant (5.34 for benzonitrile), W is the molality, and i the Van't Hoff correction factor, which is 1 for benzonitrile.
((-12.8-(-13.4)) = 5.34*W
5.34W = 0.6
W = 0.1124 mol/kg
W = m1/M1*m2
Where m1 is the mass of the solute (in g), M1 is the molar mass of the solute (in g/mol), and m2 is the mass of the solvent (in kg).
m1 = 0.551 g, m2 = 0.1 kg
0.1124 = 0.551/M1*0.1
0.01124M1 = 0.551
M1 = 49.04 g/mol
In ions atoms lose and gain electrons