-_- Compounds n Elements -_-
A compound is a substance formed when two or more elements are chemically joined. Water, salt, and sugar are examples of compounds.
When the elements are joined, the atoms lose their individual properties and have different properties from the element they are composed Of .
- Hope that this helps out alot bro .
The heat of the reaction can be calculated using the enthalpy of formation. For a 53.99-g sample of iron, the heat of the reaction is approximately -798.9 kJ.
To calculate the heat of the reaction, we need to use the concept of enthalpy of formation. The enthalpy of formation of Fe2O3(s) is -826.0 kJ/mol. We can use this value as a conversion factor to find the heat produced when 1 mole of Fe2O3(s) is formed. Since we have a 53.99-g sample of iron, we can calculate the moles of iron and use the conversion factor to find the heat of the reaction.
The molar mass of iron (Fe) is 55.845 g/mol. Therefore, the moles of iron in the sample can be calculated as:
(53.99 g) / (55.845 g/mol) = 0.9662 mol
Now, using the conversion factor:
0.9662 mol Fe × (826.0 kJ/mol) = -798.9 kJ
Therefore, the heat of the reaction 4Fe(s) + 3O2(g) → 2Fe2O3(s) when a 53.99-g sample of iron is reacted is approximately -798.9 kJ.
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The problem is solved by first converting the given mass of Fe to moles, then determining the amount of Fe2O3 formed using the stoichiometry of the reaction. With the heat formation of Fe2O3 given, the heat released in the reaction is calculated to be -399.8 kJ, indicating an exothermic reaction.
To solve the given problem, we first need to calculate the number of moles of Fe in the 53.99-g sample. The molar mass of Fe is about 55.85 g/mol, so 53.99 grams will represent approximately 0.967 moles of iron. Given the reaction 4Fe + 3O2 → 2Fe2O3, the formation of 2 moles of Fe2O3 requires 4 moles of Fe; hence a ratio of 2:4= 0.5:1 is formed. So, from 0.967 moles of iron, we get 0.967*0.5 = 0.484 moles of Fe2O3 formed.
From the problem, we know that the heat of formation of Fe2O3 is -826.0 kJ/mol. Therefore, the heat of reaction or released heat from the formation of 0.484 moles will be 0.484*-826.0 kJ/mol = -399.8 kJ. Because the value is negative, this is an exothermic reaction, releasing heat.
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THe pH of the solution containing NaF and HF would be higher than that of a solution of HF only.
The presence of NaF drives the reaction towards the HF side to reach equilibrium.
The concentration of H+ is higher in an HF solution containing NaF.
The pH of the solution containing NaF and HF would be lower than that of a solution of HF only.
The presence of the dissolved NaF does not affect the HF equilibrium reaction nor the equilibrium concentrations.
(2) the activation energy of the exothermic reaction
(3) the difference between the potential energy of the products and the potential energy of the reactants
(4) the sum of the potential energy of the products and the potential energy of the reactants
Answer: The correct answer is Option 3.
Explanation:
The net energy absorbed or released in a reaction is known as total enthalpy change of the reaction. It is designated as
It is defined as the difference between the total potential energy of the products and the total potential energy of the reactants. The equation for this is given by:
where,
= Total potential energy of the products
= Total potential energy of the reactants
Hence, the correct answer is Option 3.
Answer:
0.00496
Explanation:
on edg i just did the assignment teehee
insoluble because most Na+1 compounds are insoluble in water
soluble because all S−2 compounds are soluble in water
insoluble because there are no water soluble S−2 compounds
Answer: Option (a) is the correct answer.
Explanation:
Atomic number of sodium is 11 and its electronic distribution is 2, 8, 1. Whereas atomic number of sulfur is 16 and its electronic distribution is 2, 8, 6.
So, when both sodium and sulfur chemically combine together then it results in the formation of an ionic bond due to transfer of an electron from sodium to sulfur atom.
Sodium changes into by losing an electron and sulfur changes into by gain of two electrons from two sodium atoms.
As it is known that water is a polar solvent and all ionic substances will dissolve in water.
Therefore, we can conclude that when the compound, , is mixed with water, the is soluble because all compounds are soluble in water.
When the compound, Na2S, is mixed with water, the Na2S is soluble because all Na+1 compounds are soluble in water. The rest of the choices do not answer the question above.