Answer:
The correct answer is entropy change of the surrounding plus the entropy change of the system must be positive.
Explanation:
The term entropy is a state function.Entropy can be defined as the disorder or randomness of the molecules in a system.
A spontaneous reaction is a type of reaction which deals with the release of free energy.The change of free energy in case of spontaneous reaction is always negative.
According to the second law of thermodynamics a spontaneous reaction will occur in a system if the total entropy of both system and surrounding increases during the reaction.
Answer:
Ca²⁺ + 2 OH⁻ → Ca(OH)₂(s)
Explanation:
In chemistry, the net ionic equation is a way to write a chemical reaction whereas you write only the ions that are involved in the reaction.
When calcium chloride, CaCl₂ reacts with sodium hydroxide, NaOH to produce Ca(OH)₂ the only ions involved in the reaction are Ca²⁺ and OH⁻, thus, the balanced net ionic equation is:
<em>Ca²⁺ + 2 OH⁻ → Ca(OH)₂(s)</em>
<em>Cl⁻ and Na⁺ are not involved in the reaction and you don't have to write them.</em>
It states the fact, which we now know, that electrons are responsible for the chemical bonding. According to this theory, valency is the number of electrons present in the outermost energy shell of the atom. This energy shell is called valency shell.
<u>Answer</u>:
By tracking oxidation numbers we can identify the number electron in the atom
<u>Explanation</u>:
Tracking of electrons helps us to know when and how many electrons get transferred from one atom to other atom . Oxidation referred as the “loss of one or more electrons” by an atom. When the oxidation number of an element increases, there is a loss of electrons and that element is being oxidized. Oxidation numbers are usually written with the sign (+plus or −minus) followed by the magnitude, which is the opposite of charges on ions. In their elemental stage oxidation number of an atom is zero.
