Answer:
Explanation:
Hello,
In this case, we can compute the mole fraction of benzene by using the following formula:
Whereas n accounts for the moles of each substance, thus, we compute them by using molar mass of benzene and cyclohexane:
Thus, we compute the mole fraction:
Next, for the molality, we define it as:
Whereas we also use the moles of benzene but rather than the moles of cyclohexane, its mass in kilograms (0.08074 kg), thus, we obtain:
Or just 0.990 m in molal units (mol/kg).
Best regards.
<span>The question says,'which statement best describes how an ionic bond forms. The correct option is A. Ionic bonds are formed as a result of complete transfer of electrovalence electrons from one atom to another. The atom that donate the electron become a positively charged ion while the atom that received the atom become a negatively charged ion.</span>
Answer:
C₄F₈
Explanation:
Using their mole ratio to compute their mass
molar mass of carbon = 12.0107 g/mol
molar mass of fluorine gas = 37.99681
let x = mass of carbon
given mass of fluorine = 1.70 g
x / 12.01067 = 1.70 / 37.99687
cross multiply
x = ( 1.70 × 12) / 37.99687 = 20.4 / 37.99687 = 0.53688 g
mass of one mole of CF₂ = 0.53688 + 1.70 = 2.23688 g
number of mole of CF₂ = 8.93 g / 2.23688 = 3.992 approx 4
molecular formula of CF₂ = 4 (CF₂) = C₄F₈
Question:
Zinc metal is added to hydrochloric acid to generate hydrogen gas and is collected over a liquid whose vapor pressure is the same as pure water at 20.0 degrees C (18 torr). The volume of the mixture is 1.7 L and its total pressure is 0.987 atm. Determine the number of moles of hydrogen gas present in the sample.
A. 0.272 mol
B. 0.04 mol
C. 0.997 mol
D. 0.139 mol
E. 0.0681 mol
Answer:
The correct option is;
E. 0.0681 mol
Explanation:
The equation for the reaction is
Zn + HCl = H₂ + ZnCl₂
Vapor pressure of the liquid = 18 torr = 2399.803 Pa
Total pressure of gas mixture H₂ + liquid vapor = 0.987 atm
= 100007.775 Pa
Therefore, by Avogadro's law, pressure of the hydrogen gas is given by the following equation
Pressure of H₂ = 100007.775 Pa - 2399.803 Pa = 97607.972 Pa
Volume of H₂ = 1.7 L = 0.0017 m³
Temperature = 20 °C = 293.15 K
Therefore,
Therefore, the number of moles of hydrogen gas present in the sample is n ≈ 0.0681 moles.
