Answer:
1.48 moles of SeCl6 are needed
Explanation:
Based on the reaction:
SeCl6 + O2 → SeO2 + 3Cl2
<em>1 mole of SeCl6 reacts producing 3 moles of Cl2.</em>
To solve this question we need to use the conversion factor:
1mol SeCl6 = 3mol Cl2
As we want to produce 4.45 moles of Cl2, we need:
4.45 mol Cl2 * (1mol SeCl6 / 3mol Cl2) =
<h3>1.48 moles of SeCl6 are needed</h3>
MH₂CO₃: (1g×2) + 12g + (16g×3) = 62 g/mol
1 mol --- 62g
0,8 mol -- X
X = 0,8×62
X = 49,6g
To determine the time it takes to completely vaporize the given amount of water, we first determine the total heat that is being absorbed from the process. To do this, we need information on the latent heat of vaporization of water. This heat is being absorbed by the process of phase change without any change in the temperature of the system. For water, it is equal to 40.8 kJ / mol.
Total heat = 40.8 kJ / mol ( 1.50 mol ) = 61.2 kJ of heat is to be absorbed
Given the constant rate of 19.0 J/s supply of energy to the system, we determine the time as follows:
Time = 61.2 kJ ( 1000 J / 1 kJ ) / 19.0 J/s = 3221.05 s
Triprotic acid is a class of Arrhenius acids that are capable of donating three protons per molecule when dissociating in aqueous solutions. So the chemical reaction as described in the question, at the third equivalence point, can be show as: H3R + 3NaOH ⇒ Na3R + 3H2O, where R is the counter ion of the triprotic acid. Therefore, the ratio between the reacted acid and base at the third equivalence point is 1:3.
The moles of NaOH is 0.106M*0.0352L = 0.003731 mole. So the moles of H3R is 0.003731mole/3=0.001244mole.
The molar mass of the acid can be calculated: 0.307g/0.001244mole=247 g/mol.
<span>2.59 g/cm^3
For a face centered cubic crystal, there is 1 atom at each corner that's shared between 8 unit cells. And since there's 8 corners, that gives 8*1/8 = 1 atom per unit cell. Additionally, there are 6 faces, each with 1 atom, that's shared between 2 cells. So 6*1/2 = 3. So each unit cell has a mass of 1 + 3 = 4 atoms. The size of the unit cell will be equal to either the diameter of one atom along the edge, or the diameter of 2 atoms as the diagonal across one face of the cube, whichever results in the larger unit cell. Taking that into consideration, I will use the value of 2 for the diagonal of a face of the unit cell, resulting in the length of an edge of the unit cell being sqrt(2^2/2) = sqrt(2) = 1.414213562 times the atomic diameter. So
1.414213562 * 2 * 0.215 nm = 0.608 nm
So the volume of a single unit cell is (0.608 nm)^3
Avogadro's number of atoms will require 6.0221409x10^23 / 4 = 1.50554x10^23 unit cells and will have a mass of 87.62 grams. The volume will be
1.50554x10^23 * (0.608x10^-7 cm)^3
= 1.50554x10^23 * 0.224755712x10^-22 cm^3
= 33.83776414 cm^3
So the density is approximately 87.62 g/33.83776414 cm^3 = 2.589414585 g/cm^3, when rounded to 3 significant figures is 2.59 g/cm^3.</span>