<h2>Answer:</h2>
<em>8.67kJ/mol</em>
<h2>Explanations</h2>
The formula for calculating the amount of heat absorbed by the water is given as:

Determine the moles of KI

Since heat is lost, hence the enthalpy change of the solution will be negative that is:

Determine the enthalpy of solution in kJ•mol-1

Hence the enthalpy of solution in kJ•mol-1 for KI is 8.67kJ/mol
Stable if they have a full outer shell. 8 electrons in their outer shell
When you calculate results that are aiming for known values, the percent error formula is useful tool for determining the precision of your calculations. The formula is given by: The experimental value is your calculated value, and the theoretical value is your known value.
Answer:
Check explanation section.
Explanation:
Yes, that is true. Sodium with chemical symbol Na belongs to the group 1 on the periodic table. Group 1 elements are known as Alkali metals. Other elements in the group are Caesium, lithium, Rubidium, francium and potassium.
Neon belongs to the noble gas of group 8/0.
Sodium is very reactive and and good conductor of electricity. Sodium reacts with water for the production of hydrogen (NB: this reaction is vigorous).
2Na(s) + 2H2O ------------> 2NaOH + H2(g).
They can react with nonmetals such as the halogens. For instance;
Na + Cl2 -------------------------------> 2NaCl.
Sodium is ductile and have low melting point( but high compared to neon).
Neon is not active chemically and it has no odour and no color
I believe a possible Lewis dot structure that does not obey the octet rule, where all elements are required to have 8 electrons in their outermost shell, would be the SF4 molecule.
Sulfur can contain an more than 8 electrons, in this molecule and thus has an expanded octet.