What is the molarity of a solution prepared by dissolving 20.0 grams of naoh in sufficient water to make a solution with a total volume of 2.40 liters?
a. 0.120 m naoh
b. 0.208 m naoh
c. 0.416 m naoh
d. 0.833 m naoh

B. 0.208 M NaOH

Explanation:

Molarity is the number of moles of solute dissolved in 1 L of solution

we can use the following equation to find the molarity

molarity = number of moles of solute / volume of solution s

number of moles of NaOH dissolved - 20.0 g / 40 g/mol = 0.5 mol

volume of the solution = 2.40 L

substituting the values in the above equation

molarity = 0.5 mol / 2.40 L

molarity = 0.208 M

molarity of NaOH solution is

B. 0.208 M NaOH

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.