Answer:
- <em>2NaCl → 2Na + Cl₂, ΔH = 822 kJ </em>
Explanation:
The chemical <em>equation</em> for the <em>formation of NaCl</em> is:
- Na + (1/2) Cl₂ → NaCl , ΔH = - 411 kJ
That equation means that 1 mole of NaCl is formed by the reaction of 1 mole of Na and 1/2 mole of Cl₂, with a release of energy of 411 kJ.
The <em>decomposition</em> of <em>NaCl</em> is the inverse of the <em>formation</em> reaction; thus, you swift products and reactants and inverse the sign of the <em>change in enthalpy:</em>
- NaCl → Na + 1/2 Cl₂, ΔH = 411 kJ
Since you want the decomposition of 2 moles you multiply the equation and the ΔH by 2:
- 2NaCl → 2Na + Cl₂, ΔH = 822 kJ ← answer
Percentage
by mass is the amount in mass of a component in a mixture per 100 unit of mass of the total
mixture. Percentage by mass is the same as %w/w. In order to determine this value, we need to know the mass of the substance in question and the total mass of the sample. In this case, we have to know the mass of Fe by doing certain calculations. Then, we divide this value by the total mass given of the ore, 4.05 g and multiply by 100%. It should be expressed as follows:
Percent by mass = mass of Fe in ore / 4.05 g ore sample x 100
However, the question is lacking some information so we cannot really specify the answer.
Answer:
6
Explanation:
Formula: Al2O3
If we require 2Al2O3
We divide 2 by 3
Sorry for the shadow of phone and fingers.
Oxygen(O)
Explanation:
Oxygen is the most reactive of all the listed elements. One can determine their reactivities based on the electronegativity values.
- Every element combines with one another to attain stability like the noble gases.
- Electronegativity is the relative ease with which the atoms of elements attracts valence electrons in a chemical bond.
- On the pauling's electronegativities table of elements, carbon is 2.5, oxygen 3.5 and Cl is 3.0
- Oxygen will have the highest reactivity and the most tendency to combine with other atoms.
Learn more:
Electronegativity brainly.com/question/11932624
#learnwithBrainly
Ok well whats the questions
