Astock solution is made by dissolving 66.05 g of (nh4)2so4 in enough water to make 250 ml of solution. a 10.0 ml sample of this solution is then diluted to 50.0 ml. given that the molar mass of (nh4)2so4 is 132.1 g/mol, what is the concentration of the new solution? use mc022-1.jpg and mc022-2.jpg. 0.400 m 1.60 m 5.00 m 10.0 m

first the stock solution is prepared

we need to calculate the molar concentration of (NH₄)₂SO₄

mass of (NH₄)₂SO₄ added - 66.05 g

number of moles of (NH₄)₂SO₄ - 66.05 g / 132.1 g/mol = 0.5 mol

volume of the solution - 250 mL

molarity of solution is - number of moles / volume of solution

molarity of (NH₄)₂SO₄ - 0.5 mol / 0.250 L = 2 mol/L

10.0 mL of the stock solution is taken and diluted upto 50.0 mL

the dilution formula is used

c1v1 = c2v2

where c1 - concentration and v1 - volume of stock solution

c2 - concentration and v2 is volume of the diluted solution

substituting the values

2 mol/L x 10.0 mL = C x 50.0 mL

C = 0.4 mol/L

concentration of new solution is 0.4 M

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.