Answer is: the molar mass od sodium carbonate (Na₂CO₃) is 106.0 g/mol.
M(Na₂CO₃) = 2 · Ar(Na) + Ar(C) + 3 · Ar(O).
M(Na₂CO₃) = 2 · 23 + 12 + 3 · 16 · g/mol.
M(Na₂CO₃) = 46 + 12 + 48 · g/mol.
M(Na₂CO₃) = 106 g/mol; molar mass of sodium carbonate.
Ar is relative atomic mass (the ratio of the average mass of atoms of a chemical element to one unified atomic mass unit) of an element.
The answer would be the third one listed, Refraction
Answer:
1) The vapor density of the organic compound is approximately 12.57
2) The relative molar mass (RMM) of the organic compound is approximately 25.14 grams
Explanation:
1) The mass of the balloon filled with dry hydrogen = 35 grams
The mass of the balloon filled with vapor of an organic compound = 440 grams
The vapor density = (Weight of a given volume of gas)/(Weight of equal volume of hydrogen)
The vapor density of the organic compound = (440)/(35) ≈ 12.57
The vapor density of the organic compound ≈ 12.57
2) The relative molar mass (RMM) = 2 × vapor density
The relative molar mass (RMM) of the organic compound = 2 × vapor density of the organic compound
The relative molar mass (RMM) of the organic compound ≈ 2 × 12.57 ≈ 25.14 grams
The relative molar mass (RMM) of the organic compound ≈ 25.14 grams
Answer:vv

Explanation:
The expression for the deBroglie wavelength is:
Where,
is the deBroglie wavelength
h is Plank's constant having value
m is the mass of =
v is the speed.
Wavelength = 5400 Å = 
Applying in the equation as:-


To answer the question above, we take note first that every mole of PCl₃ contains 3 atoms of Cl. First, we divide the given number by 3.
3.68 x 10²⁵ / 3 = 1.227 x 10²⁵
Then, we divide the answer by the Avogadro's number which is equal to 6.022 x 10²³. That is,
1.227 x 10²⁵ / (6.022 x 10²³) = 20.37
Thus, there are 20.37 mol of PCl₃.