Answer: D
An equal number of atoms must be on both sides of the equation.
Because matter cannot be created nor destroyed.
Answer:
the enthalpy of the second intermediate equation is halved and has its sign changed.
Explanation:
Let us take a look at the first and second intermediate reactions as well as the overall reaction equation for the process under review;
First reaction;
Ca (s) + CO₂ (g) + ½O₂ (g) → CaCO₃ (s) ΔH₁ = -812.8 kJ
Second reaction;
2Ca (s) + O₂ (g) → 2CaO (s) ΔH₂ = -1269 kJ
Hence the overall equation is now;
CaO (s) + CO₂ (g) → CaCO₃ (s) ΔH = ?
According to the Hess law of constant heat summation, the enthalpy of the overall reaction is supposed to be obtained as a sum of the enthalpy of both reactions but this will not give the enthalpy of the overall reaction in this case. The enthalpy of the overall reaction is rather obtained by halving the enthalpy of the second intermediate reaction and reversing its sign before taking the sum as shown below;
Enthalpy of Intermediate reaction 1 + ½(- Enthalpy of Intermediate reaction 2) = Enthalpy of Overall reaction
The formula of ionic compound made from sodium (Na) and iodine (l) is
NaI
<em><u>Explanation</u></em>
- An ionic compound is are compounds made up of ions.
- The ions are atoms or ions that loses electron to form cation or gain electron to form anion.
- Metal for this case loses electron while non metal gain electrons
- In Nal Na <em>( a Metal</em>) loses one electron while I <em>(non metal) </em>gain one electron to form an ionic compound.
Answer:
1.13 moles Au
Explanation:
Moles Au = 6.80x10²³atoms / 6.023x10²³atoms/mole = 1.13 moles Au