<u>Answer:</u> The balanced chemical equation for the reaction of nitric acid and calcium hydroxide is written below.
<u>Explanation:</u>
A balanced chemical equation is defined as the equation in which total number of individual atoms on the reactant side is equal to the total number of individual atoms on product side.
The balanced chemical equation for the reaction of nitric acid and calcium hydroxide follows:
By Stoichiometry of the reaction:
2 moles of nitric acid reacts with 1 mole of calcium hydroxide to produce 1 mole of calcium nitrate and 2 moles of water molecule.
Hence, the balanced chemical equation for the reaction of nitric acid and calcium hydroxide is written below.
Answer : The value of 
for the reaction is +571.6 kJ/mole.
Explanation :
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The given chemical reaction is,
Now we have to determine the value of for the following reaction i.e,
According to the Hess’s law, if we reverse the reaction then the sign of change.
So, the value 
for the reaction will be:
Hence, the value of for the reaction is +571.6 kJ/mole.
Answer:
The main difference is their energy level, 2s orbital is higher than 1s orbital.
Raise the boiling temperature
Answer:
Single replacement reaction (aka single displacement reaction)
Explanation:
In a single replacement reaction, one element is substituted for another in a compound to create a new compound and a new element in the products. The general form is:
A + BC --> B + AC
In the case of this question, Cr and Fe "trade places."
