Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Can you help me understand the ratio to all this: Calcium phosphate-based cement

ID: 952076 • Letter: C

Question

Can you help me understand the ratio to all this: Calcium phosphate-based cements were prepared by hand mixing in an agate mortar. Cement pastes were prepared by mixing solid and liquid phase CPCs with a liquid-to-powder ratio (L/P) of 0.4 (wt/wt). The liquid phase was composed of 1 M Na2HPO4 (look at note) and 0–20% (look at note) of citric acid. All calcium phosphate formulations had a 1.67 Ca/P ratio. (Note: I have Na2HPO4 stock solution prepared) (Note: I am going to be doing 10% of citric acid. Citric Acid for 10% requires 52g CitricAcid and 468 ml DH20) I want to know how much do need of each of the elements: how much of Na2HPO4 with Citric Acid (volume).. how much of the powder (in grams)?

Explanation / Answer

CPC : it is calcium phosphate cement ( so in powder we will take some calcium phosphate compound)

(i) We need to prepare a liquid to powder ratio of 0.4 wt / wt

so if we are taking 0.4 grams of liquid then we will take 10 grams of powder

(ii) the liquid is made from Na2HPO4 and 10% citric acid

If you are taking 52 grams of citric acid in 468mL of DH2O, then we can preapare the same as

Dissolve 52 gram of citric acid in 468mL of already prepared stock solution of Na2HPO4.

So now you have 1M Na2HPO4- 10% citric acid solutio with you

(iii) Take 4mL of the same solution (above prepared) , assuming the density of solution will be equal to water.

(iv) Add 10 grams of calcium phosphate powder to it.

So the paste will have the desired composition.