K3PO4와 Ca3(PO4)2의 당량수(=당량, equivalent weight), 노르말농도

K3PO4와 Ca3(PO4)2의 당량수(=당량, equivalent weight), 노르말농도

 

 

1) Calculate the equivalent weight for tribasic potassium phosphate, K3PO4 (MW = 212.27 g/mol).

 

Answer) K3PO4 has three potassium ions each with a valence of 1 or one phosphate ion with a valence of 3.

▶ equivalents/mol = 3

▶ equivalent weight = 212.27 / 3 = 70.76 g/eq

 

 

2) What is the equivalent weight for Ca3(PO4)2 (MW = 310.18 g/mol).

 

Answer) The compound has 3 ions of calcium each with a valence of 2 or it has 2 phosphate ions each with a valence of 3.

▶ equivalents/mol = 6

▶ equivalent weight = 310.18 / 6 = 51.70 g/eq