Which of the following is the formation reaction for CaO(s) ?
A. Ca2+(aq) + O2–(aq) CaO(s)
B. Ca(s) + .5O2(g) CaO(s).
C. CaO(s) Ca(s) + .5O2(g)
D. 2 Ca(s) + O2(g) 2CaO(s)
E. 2 CaO(s) 2 Ca(s) + O2(g)
Left with B and D. Please Help
B isn't balanced so throw it out.
That leaves D as the only possible answer.
By the way, you should show the arrows; otherwise, we don't know the difference between reactants and products.
Although I would pick D as the answer, I looked for
Ca + 1/2 O2 ==> CaO since these usually are quoted for 1 mol of substance and not 2 mols of substance.
The formation reaction for CaO(s) can be determined by balancing the equation and ensuring that the reactants form the desired product CaO(s).
Option B: Ca(s) + 0.5O2(g) → CaO(s)
Option D: 2Ca(s) + O2(g) → 2CaO(s)
To determine the correct formation reaction, we need to check if the reactants form the product as a single compound (CaO) and if the equation is balanced.
In option B, Ca(s) and O2(g) react to form CaO(s). This equation is balanced, and CaO is formed as a single compound. Therefore, option B is a possible formation reaction for CaO.
In option D, 2Ca(s) and O2(g) react to form 2CaO(s). This equation is also balanced, and CaO is formed as a single compound. Therefore, option D is also a possible formation reaction for CaO.
So, both options B and D are valid formation reactions for CaO.
To determine the formation reaction for CaO(s), we need to find the balanced chemical equation that shows the formation of CaO from its elements in their standard states.
Let's break down options B and D to determine which one represents the correct formation reaction:
Option B: Ca(s) + 0.5O2(g) → CaO(s)
Option D: 2Ca(s) + O2(g) → 2CaO(s)
To compare these options, we need to make sure that the equation is balanced and represents the formation reaction of CaO(s).
Option B does not have a balanced equation. It has Ca on the left side but only one Ca on the right side. This does not represent a formation reaction since Ca is not being produced or formed.
On the other hand, Option D is balanced, and it represents the formation of CaO from its elements in their standard states. It shows that two Ca atoms react with one O2 molecule to produce two CaO molecules.
Therefore, the correct answer is Option D:
2 Ca(s) + O2(g) → 2 CaO(s)
This balanced equation represents the formation reaction for CaO(s).