Answer:
0.014mol
Explanation:
Given parameters:
Mass of Na₂CO₃ = 1.5g
Unknown:
Number of moles = ?
Solution:
Number of moles of a compound is mathematically expressed as;
Number of moles =
Molar mass of Na₂CO₃ = 2(23) + 12 + 3(16) = 106g/mol
Number of moles =
= 0.014mol
Answer:
vHe / vNe = 2.24
Explanation:
To obtain the velocity of an ideal gas you must use the formula:
v = √3RT / √M
Where R is gas constant (8.314 kgm²/s²molK); T is temperature and M is molar mass of the gas (4x10⁻³kg/mol for helium and 20,18x10⁻³ kg/mol for neon). Thus:
vHe = √3×8.314 kgm²/s²molK×T / √4x10⁻³kg/mol
vNe = √3×8.314 kgm²/s²molK×T / √20.18x10⁻³kg/mol
The ratio is:
vHe / vNe = √3×8.314 kgm²/s²molK×T / √4x10⁻³kg/mol / √3×8.314 kgm²/s²molK×T / √20.18x10⁻³kg/mol
vHe / vNe = √20.18x10⁻³kg/mol / √4x10⁻³kg/mol
<em>vHe / vNe = 2.24</em>
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I hope it helps!
Given:
<span>M1 = 6.5 kg of books
</span><span>M2 = 1.5 kg of CDs
</span><span>M3 = 2.0 kg of DVDs
Required: percent by mass of each object
Solution:
First, we calculate the total mass.
M = 6.5 kg + 1.5 kg + 2.0 kg = 10 kg
Percent by mass is calculated by getting the ration of the mass of an object and the total mass multiplied by 100 to get the percent.
%M1 = 6.5 / 10 x 100 = 65%
%M2 = 1.5/10 x 100 = 15%
%M3 = 2.0/10 x 100 = 20%</span>
Iron rusts when exposed to air → chemical property
<u>Answer:</u> The expression for equilibrium constant is ![K_{eq}=\frac{[HOCl]^2}{[H_2O][Cl_2]^2}](https://tex.z-dn.net/?f=K_%7Beq%7D%3D%5Cfrac%7B%5BHOCl%5D%5E2%7D%7B%5BH_2O%5D%5BCl_2%5D%5E2%7D)
<u>Explanation:</u>
Equilibrium constant is defined as the ratio of concentration of products to the concentration of reactants each raised to the power their stoichiometric ratios. It is expressed as 
For the general chemical equation:

The expression for
is given as:
![K_c=\frac{[C]^c[D]^d}{[A]^a[B]^b}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7B%5BC%5D%5Ec%5BD%5D%5Ed%7D%7B%5BA%5D%5Ea%5BB%5D%5Eb%7D)
For the given chemical reaction:

The expression for
is given as:
![K_{eq}=\frac{[HOCl]^2[HgO.HgCl_2]}{[HgO]^2[H_2O][Cl_2]^2}](https://tex.z-dn.net/?f=K_%7Beq%7D%3D%5Cfrac%7B%5BHOCl%5D%5E2%5BHgO.HgCl_2%5D%7D%7B%5BHgO%5D%5E2%5BH_2O%5D%5BCl_2%5D%5E2%7D)
The concentration of solid is taken to be 0.
So, the expression for
is given as:
![K_{eq}=\frac{[HOCl]^2}{[H_2O][Cl_2]^2}](https://tex.z-dn.net/?f=K_%7Beq%7D%3D%5Cfrac%7B%5BHOCl%5D%5E2%7D%7B%5BH_2O%5D%5BCl_2%5D%5E2%7D)