# How do you make a Na2HPO4 buffer?

## How do you make a Na2HPO4 buffer?

METHOD

1. Dissolve 35.61 g of Na2HPO4•2H2O and 27.6 g of NaH2PO4•H2O separately in H2O.
2. Adjust the volume of each solution to 1000 mL. Store the stock solutions for up to 6 mo at 4°C.
3. To prepare the buffer, mix the stock solutions as follows: i.
4. Check the pH of the solution at room temperature.

What is the pH of a solution of 30 mm NaH2PO4 and 60 mm Na2HPO4?

Phosphate Buffer Preparation Table – 0.2 M solution

Potassium Phosphate Monobasic Anhydrous g/L Sodium Phosphate Dibasic Heptahydrate g/L 23 °C pH
9.36 32.73 7.0
7.92 35.95 7.1
6.72 38.63 7.2
5.52 41.31 7.3

### Is NaH2PO4 and NaOH a buffer?

A buffer is most effective at its pKa, which is the point where [salt] = [acid]. To make a buffer from this solution, it will be necessary to titrate it with a base, to a pH closer to the pKa. NaOH is a suitable base because it maintains sodium as the cation: NaH2PO4 + NaOH–+ Na2HPO4 + H20.

How do you make a 7.4 pH phosphate buffer?

Saline pH 7.4, Phosphate-buffered: Dissolve 2.38 g of disodium hydrogen phosphate, 0.19 g of potassium dihydrogen phosphate and 8.0 g of sodium chloride in sufficient water to produce 1000 ml. Adjust the pH, if necessary.

## How do you make 1m Na2HPO4?

Protocol II: 1 M Sodium Phosphate Buffer Stock Solution (1 liter)

1. Solution A: Dissolve 138.0 g NaH2PO4–H2O in 1 liter dH2O (pH 7.0).
2. Solution B: Dissolve 142.0 g Na2HPO4 in 1 liter dH2O (pH 7.0).
3. Mix 423 ml Solution A with 577 ml Solution B.
4. Autoclave and store at room temperature.

How do you make a 1m phosphate buffer?

### Can NaH2PO4 and Na2HPO4 make a buffer?

A buffer must have an acid/base conjugate pair. b) NaH2PO4 and Na2HPO4 are an acid/base conjugate pair. They will make an excellent buffer.

Why is NaH2PO4 and Na2HPO4 a good buffer?

NaH2PO4 is much more acidic than Na2HPO4, hence NaH2PO4 acts as an acid while Na2HPO4 acts a salt of NaH2PO4 with a strong base NaOH. Hence mixture is having a weak acid NaH2PO4 and its salt with a strong base Na2HPO4 and that’s why mixture acts as an acidic Buffer.

## How do you make a 50mM sodium phosphate buffer?

To prepare 50mM phosphate buffer with 7.0pH:

1. Prepare 800 mL of distilled water in a suitable container.
2. Add 7.744 g of Na2HPO4•7H2O to the solution.
3. Add 2.913 g of NaH2PO4•H2O to the solution.
4. Adjust solution to final desired pH using HCl or NaOH.
5. Add distilled water until volume is 1 L.

Is NaH2PO4 amphoteric?

Na2HPO4 is amphoteric, which means it can act as a base or as a acid depending on which substance they react with.

### How do you make Na2HPO4 7H2O from Na2HPO4?

7H2O you dissolve 268.07 gram in 1 L, if you have Na2HPO4. 12H2O you dissolve 358,14 g/mol. If your buffer requires 2.9 g of Na2HPO4*12H2O you just need, asbasically explained by Wolfgang Schechinger , 268.07/358.14 * 2.9 gram Na2HPO4. 7H2O (so 2.17 gram).

What is the pH of NaH2PO4 buffer?

0.1 M sodium phosphate buffer (pH 7.4) Add 3.1 g of NaH 2 PO 4 •H 2 O and 10.9 g of Na 2 HPO 4 (anhydrous) to distilled H 2 O to make a volume of 1 L. The pH of the final solution will be 7.4.

## How do you make a sodium phosphate buffer?

Sodium phosphate. 1 M sodium phosphate buffer (pH 6.0–7.2) Mixing 1 M NaH 2 PO 4 (monobasic) and 1 M Na 2 HPO 4 (dibasic) stock solutions in the volumes designated in the table below results in 1 L of 1 M sodium phosphate buffer of the desired pH. To prepare the stock solutions, dissolve 138 g of NaH 2 PO 4 •H 2 O (monobasic;

What is the meaning of the name Na2HPO4?

Na 2 HPO 4: Disodium phosphate (DSP), or sodium hydrogen phosphate, or sodium phosphate dibasic, is the inorganic compound with the formula Na 2 HPO 4. It is one of several sodium phosphates.

### What is the pKa of a phosphate buffer?

A phosphate buffer solution is especially useful for biological applications, which are especially sensitive to pH changes since it is possible to prepare a solution near any of three pH levels. The three pKa values for phosphoric acid (from the CRC Handbook of Chemistry and Physics) are 2.16, 7.21, and 12.32.