Answer:
E
Explanation:
Here in this question, what we will do is to select which of the pairs that do not correlate.
A. Enthalpy and heat content
This two terms are at par with each other. By definition, the enthalpy of a system simply is the total amount of heat content it has.
B. Endothermic reaction and +H
These two terms are at par with each other. An endothermic reaction is one in which heat is absorbed from the surroundings. It has a positive value for the heat content i.e the enthalpy is positive and thus H is positive.
C. Exothermic reaction and -H
An exothermic reaction is one in which heat is released to the environment. It usually has a negative value for the enthalpy and thus the value of H is negative.
D. High energy and High Stability
These two terms are not at par. When an entity has or is of high energy, it is usually unstable. An entity at a higher energy level will not be stable until it goes to a lower level of energy.
Thus higher energy level is associated with lesser stability while lower energy levels are associated with higher stability. The lesser the energy of an entity, the higher its stability.
This makes the option our answer.
The mass of 1.72 mol of magnesium fluoride is 107 grams.
To determine the mass of 1.72 mol of magnesium fluoride, we first need the chemical formula of magnesium fluoride. Magnesium forms a +2 ion (Mg+2) and fluoride forms a -1 ion (F-1). Since all compounds formed from ions have to be electrically neutral, we need 2 fluoride ions and 1 magnesium ion. Therefore, the formula for magnesium fluoride is MgF2.
Now we need to determine the molar mass of the compound from the molar mass values from the periodic table. Let's use a table to calculate this molar mass.
Molar mass of MgF2
Element Molar Mass (g/mol) Quantity Total (g/mol)
Mg 24.31 1 24.31
F 19.00 2 38.00
Total molar mass of MgF2 = 24.31 g/mol + 38.00 g/mol = 62.31 g/mol
This is the mass of one mole of the substance. If we have 1.72 mols of it, we multiply 1.72 by 62.31.
1.72 mol (62.31 g/mol) = 107 grams
We rounded to 107 to keep the correct number of significant digits in our answer.
<span>An azeotrope is a mixture of two or more liquids whose proportions remain the same when vaporized. Because of this, fractional distillation is unable to purify ethanol.</span>
Answer:
34.59 % Al; 61.54 % O; 3.877 % H
Explanation:
% by mass = mass of element/total mass × 100 %
Let's rewrite the formula of Al(OH)₃ as AlO₃H₃.
Set up a table for easy calculation.
<u>Atom</u> <u> Mass/u </u> <u>Subtotal
</u>
1Al 1 × 26.98 = 26.98 u
3O 3 × 16.00 = 48.00 u
3H 3 × 1.008 = <u> 3.024 u
</u>
Total = 78.004 u
Mass % Al = 26.98/78.004 × 100 % = 34.59 %
Mass % O = 48.00/78.004 × 100 % = 61.54 %
Mass % H = 3.024/78.004 × 100 % = 3.877 %
I think the answer could.. actually nvm I don’t know
