Answer:
The mole fractions:




Explanation:
The reaction described is:

The limiting reactant is the HBr (oxygen is in excess).
a) The mass (in moles) balance for this sistem:
(the 0.78 is because of the fractional conversion)

(the 1.25 is because of the oxygen excess)
There is only one degree of freedom in this sistem, you can either deffine the moles of HBr you have or the moles of Br2 you want to produce. The other variables are all linked by the equations above.
b) Base of calculation 100 mol of HBr:




The mole fractions:




The solubility of a substance in water is dependent on the temperature. Thus for
1 & 2: Temperature is the independent variable (the one that changes in the first place) and Solubility is a dependent variable (a variable that changes in response to changes in the independent variable.)
The graph: by convention you shall label the horizontal axis with the independent variable and the vertical axis with the dependent variable. For clarity's sake you shall use the finest scale possible that accommodates for all data provided for both axis. Plot the data points on the graph as if they are points on a cartesian plane.
My teacher made no detailed requirements on the phrasing on titles of solubility curve plots; however, like most other graphs in chemistry, the title shall specify the name of variables presented in this visualization. For instance, "the solubility of
under different temperatures" might do. You shall refer to your textbooks for such convention.
It is necessary to interpolate to find the solubility at a temperature not given in the table. Start by connecting all given data points with a smooth line; find the vertical line corresponding to temperature = 75 degree Celsius and determine the solubility at the intersection of the vertical line and the trend line. That point shall approximates the solubility of the salt at that temperature.
Answer:
Mass = 20 g
Explanation:
Given data:
Number of moles of He = 5 mol
Mass of He = ?
Solution:
Formula:
Number of moles = mass/ molar mass
Molar mass = 4 g/mol
by putting values,
5 mol = Mass / 4 g/mol
Mass = 5 mol × 4 g/mol
Mass = 20 g
Answer:
A. One unpaired electron
B. 5 unpaired electrons
Explanation:
In A ,Fe is in +3 oxidation state and Electronic configuration- [Ar]3d5
And NO2 is a strong field ligand hence it causes pairing in t2g orbitals and results one unpaired electron in dZX orbital.
In B, also Fe is in +3 oxidation state but F is weak field ligand hence causes no pairing of Electrons hence it results 5 unpaired electrons with electronic configuration t2g^3 eg^2
Activation energy is defined as the least amount of energy that is needed to be available in a chemical system with potential reactants in order to result a chemical reaction. Therefore, the correct answer would be the first option: the heat released in a reaction.