In the making stock solutions from solids problem, make a 100 ml solution that is 2.5 M of the Cl- ion using NaCl and make a 100 mL solution that is 0.5 M of the Cl- ion using MgCl2. Show your calculations and give details about the equipment used, which solutions you mixed together, and amounts of each.

Explanation:

1) Molarity of the chloride solution = 2.5 M

Volume of the chloride solution = 100 mL = 0.100 L ( 1mL = 0.001 L)

Moles of chloride ions = n

1 mole of chloride ions are obtained from 1 mole NaCl,then 0.25 mol  of chloride ions will be obtained from  :

of NaCl

Mass of 0.25 moles of NaCl :

0.25 mol ×  58.5 g/mol = 14.62 g

In a dry 100 mL volumetruc flask add weighed 14.62 grams of NaCl and small amount of water to dissolve it completely. After this add the water upto mark of 100 mL to form chloride solution of 0.25 M.

2) Molarity of the chloride solution = 0.5 M

Volume of the chloride solution = 100 mL = 0.100 L ( 1mL = 0.001 L)

Moles of chloride ions = n

2 mole of chloride ions are obtained from 1 mole ,then 0.05 mol  of chloride ions will be obtained from  :

of

Mass of 0.025 moles of :

0.025 mol ×  95 g/mol = 2.375 g

In a dry 100 mL volumetruc flask add weighed 2.375 grams of and small amount of water to dissolve it completely. After this add the water upto mark of 100 mL to form chloride solution of 0.5 M.

the seeing the electronic configuration we can say that the element is fluorine.

fluorine is the most electronegative element in the periodic table.

but by only seeing the configuration we cannot say about its reactivity because we don't know if its configuration after excitation or by addition of electrons.

but if not then, it is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. as the most electronegative element, it is extremely reactive: almost all other elements, including some noble gases, form compounds with fluorine.