1.8e-6 this should be the correct answer according to my mass converter.
Explanation:
The given data is as follows.
= 286 kJ = 
= 286000 J
,

Hence, formula to calculate entropy change of the reaction is as follows.

= ![[(\frac{1}{2} \times S_{O_{2}}) - (1 \times S_{H_{2}})] - [1 \times S_{H_{2}O}]](https://tex.z-dn.net/?f=%5B%28%5Cfrac%7B1%7D%7B2%7D%20%5Ctimes%20S_%7BO_%7B2%7D%7D%29%20-%20%281%20%5Ctimes%20S_%7BH_%7B2%7D%7D%29%5D%20-%20%5B1%20%5Ctimes%20S_%7BH_%7B2%7DO%7D%5D)
= ![[(\frac{1}{2} \times 205) + (1 \times 131)] - [(1 \times 70)]](https://tex.z-dn.net/?f=%5B%28%5Cfrac%7B1%7D%7B2%7D%20%5Ctimes%20205%29%20%2B%20%281%20%5Ctimes%20131%29%5D%20-%20%5B%281%20%5Ctimes%2070%29%5D)
= 163.5 J/K
Therefore, formula to calculate electric work energy required is as follows.
= 
= 237.277 kJ
Thus, we can conclude that the electrical work required for given situation is 237.277 kJ.
I think the answer is (1) Co. Because the element of Cobalt also has 2 electrons at the outer layer which is the same as Calcium. And the outer layer is an important factor which can affect the property of an element.
Answer:
Acid + Base -------> Salt + Water
Explanation:
The reaction between an acid and bases is called a neutralization reaction. The result of the reaction is salt and water. For example, when hydrochloric acid(acid) and sodium hydroxide(base) react they form sodium chloride(salt) and water. Also, heat is evolved.
Example:
HCl + NaOH ----------> NaCl + H2O
HCl is hydrochloric acid.
NaOH is sodium hydroxide which is a base.
NaCl is sodium chloride which is a salt.
H2O is water.