I believe it's helium at 0.49 A
The dilution factor of the unknown sample is 10. The dilution factor of a solution refers to the ratio of the final volume of the now diluted solution to the initial volume of the of the initial concentrated solution.
Mathematically;
The dilution factor is given by the formula;
Dilution factor = Final volume of the now diluted solution/ Initial volume of more concentrated solution
Final volume of the now diluted solution = 100.0 ml
Initial volume of more concentrated solution = 10.00 ml
Dilution factor = 100.0 ml/10.00 ml
Dilution factor = 10
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Answer:

Explanation:
Hello,
In this case, since the undergoing chemical reaction is:

The corresponding moles of carbon dioxide occupying 40.0 mL (0.0400 L) are computed by using the ideal gas equation at 273.15 K and 1.00 atm (STP) as follows:

Then, since the mole ratio between carbon dioxide and calcium carbonate is 1:1 and the molar mass of the reactant is 100 g/mol, the mass that yields such volume turns out:

Regards.
Answer:
C₂H₃Cl₃O₂
Explanation:
Given parameters:
Percentage composition:
14.52% C
1.83% H
64.30% Cl
19.35% O
Molar mass = 165.4 g/mo
Unknown:
Empirical formula = ?
Solution:
The empirical formula of a compound is the simplest formula of a compound. To solve this problem, let us follow the process below:
C H Cl O
%composition 14.52 1.83 64.3 19.35
Molar mass 12 1 17 16
number of
moles 14.52/12 1.83/1 64.3/3.5 19.35/16
1.21 1.83 1.81 1.21
Divide by
the smallest 1.21/1.21 1.83/1.21 1.81/1.21 1.21/1.21
1 1.51 1.51 1
multiply
by 2 2 3 3 2
Empirical formula C₂H₃Cl₃O₂
C₂H₄ + 3O₂ = 2CO₂ + 2H₂O
V(C₂H₄) = 270 L
V(O₂)=3V(C₂H₄)
V(O₂)=3*270=810 L