Answer:
d. 97.60 g
Explanation:
Given parameters:
Number of moles of formaldehyde = 3.25moles
Ratio:
C H O
1 2 1
Unknown:
Mass of this sample = ?
Solution:
The empirical formula of a compound is its simplest formula. It is the simplest whole number ratio of the atoms in a given substance.
The molecular formula is the actual formula of the compound.
Since the molecular and empirical formula are the same here, the formula of the compound is;
CH₂O
To find the mass of the formaldehyde, use the expression below;
Mass = number of moles x molar mass
molar mass of CH₂O = 12 + 2(1) + 16 = 30g/mol
Mass = 3.25 x 30 = 97.5g
Answer:
Conversion factor;
Molar mass;
Avogadro's constant and molar mass
Explanation:
- Firstly, an intermediate step is to define the conversion factor that will be then used in a conversion technique called dimensional analysis in order to convert from one unit to another. An example of a conversion factor would be, for example, 1 L = 1000 mL, which can be manipulated as a fraction, either
or
; - Secondly, in order to convert mass to moles, we need to know the molar mass of a compound which has a units of g/mol (that is, it shows how many grams we have per 1 mole of substance.
- Thirdly, Avogadro's constant,
tells us that there is
number of molecules or atoms in 1 mole of substance. We need two conversion factors to convert the number of molecules to a mass: firstly, we need to convert the number of molecules into the number of moles using Avogadro's constant and then we need to use the molar mass to convert the moles obtained into mass.
Speed is the distance travelled per unit time.
If the gases are at the same temperature and pressure, the ratio of their effusion rates is directly proportional to the ratio of the square roots of their molar masses:
<h3>Graham's law of diffusion </h3>
This states that the rate of diffusion of a gas is inversely proportional to the square root of the molar mass i.e
R ∝ 1/ √M
R₁/R₂ = √(M₂/M₁)
Where
- R₁ and R₂ are the rates of the two gas
- M₁ and M₂ are the molar masses of the two gas
From the Graham's law equation, we can see that the ratio of the rates of effusion of the two gases is directly proportional to the square root of their molar masses
Learn more about Graham's law of diffusion:
brainly.com/question/14004529
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