How many liters of water are needed to make 6.3 M solution of NaCl made with 5,128 grams of Na Cl (molar mass = 58)?

0.014 Liters needed

Explanation:

Given 5.128 grams NaCl + ?Water Solvent => 6.3M solution

Solution Concentration = moles solute/liter solution = Molarity (M)

=> Molarity (M) = 6.3M = (5.128g NaCl/58g·mole⁻¹) / Volume of Sol'n (L)

∴ Vol of Solution = Vol of Water Solvent needed

= (5.128g NaCl/58g·mole⁻¹) / 6.3M

= 0.0884 mole NaCl / 6.3 mol/L = 0.014 Liters water solvent.

Method of Mixing:

Transfer 5.128g NaCl into mixing container and add solvent water up to but not to exceed 0.014 Liters (=14 ml) total volume. Mix till homogeneous.

answer: the enthalpy of the overall chemical reaction is +87.88 kj or +88 kj.

according to hess's law, the overall enthalpy of a reaction is the difference between the sum of enthalpy values of all the products and the sum of enthalpy values of all the reactants.

δh(reaction) = ∑nδh(products) - ∑nδh(reactants)

δh(reaction) = [δh +δh] - [δh]

δh(reaction) = [1(-287.02) + 1(0) ] - [1(-374.9)] kj = +87.88 kj

here, δh (pcl3) = -287.02 kj, δh(cl2) = 0, δh(pcl5) = -374.9 kj

therefore, enthalpy of the overall reaction is +87.88 kj or +88 kj.