What mass of k2co3 is needed to prepare 200. ml of a solution having a potassium ion concentration of 0.150 m

2.07 grams

Explanation:

We know that the molecular mass of is 138.205 grams.

In order to find out how many grams we need to make 200 mL having a potassium ion concentration of 0.150, we need to find the number of moles first.

M = moles / liters

0.150 = x / 0.200

x = 0.03 moles

Since there are 2 potassium atoms in each molecule of so we will divide this number by half and multiply it by the molecular mass.

0.03/2 = 0.015 moles

Mass of needed = 0.015 × 138.205 = 2.07 grams

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.