Question

In: Nursing

Rx: Castor oil 10% (v/v) Tween 80 and Span 20 2% (w/v) Simple syrup qs 50...

Rx:
Castor oil	10% (v/v)
Tween 80 and Span 20	2% (w/v)
Simple syrup	qs 50 mL

How many gram(s) of Span 20 are needed to prepare for the prescription, given that the required HLB for the emulsion is 10, Span 20 has an HLB of 8.6, and Tween 80 has an HLB of 15?

Expert Solution

Solution :

HLB means Hydrophilic - Lipophilic Balance.HLB scale range from 0 to 20.

Most important aspect of HLB system is that HLB values are additive if the amount of each in a blend is taken into account. Thus blends of high and low HLB surfactants can be used to obtain the required HLB of an oil.

Span has lipophilic properties and have low HLB value of 1.8 - 8.6. here Span 20 HLB value is 8.6

Tween has hydrophilic properties , it is Polyoxyethylene derivative of span. it has high HLB vlue is 9.6 - 16.7 . Tween 80 HLB value is 15.

Assume Tween 80 (HLB 15 ) is A and Span 20 (HLB 8.6) is B

The perecentage equation form is A = 100 ( X - HLB_B ) ( HLB_A - HLB_B )

B = 100 - A

Where X = required HLB value of the emulsion = 10

HLB_A = HLB value of Tween 80 = 15

HLB_B = HLB value of Span 20 = 8.6

Mixture of Tween 80 and Span 20 weight is 2grams.

Equation is A = 100 ( X - HLB_B ) ( HLB_A - HLB_B )

= 100 ( 10 - 8.6) ( 15 - 8.6)

= 100 ( 1.4) ( 6.4)

= 140 6.4

A = 21.8%

B = 100 - A

= 100 - 21.8

B = 78.2%

Weight of tween 80 (A) and Span 20 is needed to form emulsion with HLB 10 are calculated by

Weight of tween 80 (A) = percentage of A weight of mixture 100

= 21.8 2 100

= 43.6 100

Weight of tween 80 (A) = 0.436 grams

Weight of Span 20 (B) = weight of mixture - Weight of tween 80 (A)

= 2 - 0.436

Weight of Span 20 (B) = 1.564 grams

1.564 gms of Span 20 is needed to prepare for the prescription,given that the required HLB for the emulsion is 10.

Nightingale answered 1 year ago

Rx: Pilocarpine nitrate 2% (w/v) Boric acid q.s. Rx Sterile water for injection q.s 20 mL...

Rx: Pilocarpine nitrate 2% (w/v) Boric acid q.s. Rx Sterile water for injection q.s 20 mL Sig: One (1) gtt OU t.i.d.. How much boric acid (in milligrams) is needed to make this prescription isotonic? (E-value pilocarpine nitrate = 0.23, E-value boric acid = 0.52). Round your answer to the nearest whole number.

A pharmacist is asked to formulate the simple syrup containing 55% (w/v) of sucrose. Answer the...

A pharmacist is asked to formulate the simple syrup containing 55% (w/v) of sucrose. Answer the following questions regarding the compounding of this formulation: a) Can this formulation be considered self-preserving? explain your answer b) How much alcohol USP is required to add to this formulation if the prescription calls for 750 mL of the syrup. Show calculations.

V owns 80% and his friend, W, owns 20% of a partnership. After transferring 30% of...

V owns 80% and his friend, W, owns 20% of a partnership. After transferring 30% of the capital and profits interest to his son, R, V's interest drops down to 50% of the partnership. Partnership profits of $200,000 for the year were allocated as follows: $100,000 to V, $60,000 to R, and $40,000 to W. Two years later, an IRS audit revealed the following: •Only V performs services for the partnership and they were worth $52,000. •Ending capital accounts were...

20 mL of 15% HCl(v/v) 1000 mL of 10% HCl(w/v) Give the percentages of the following:...

20 mL of 15% HCl(v/v) 1000 mL of 10% HCl(w/v) Give the percentages of the following: 130 mg of HCl + 90 g of H20 How many grams of sodium chloride are there in 0.75 L of a 5% solution? What weight of NaOH would be required to prepare 500 mL of a 1.5 M solution? A solution contains 25 g NaCl/L. What is its molarity? What is the molecular weight of NaCl? What is the equivalent weight of NaCl?...

An N-Channel device has K’n = 50 µA / V^2, Vt = 0.8 V and W/L...

An N-Channel device has K’n = 50 µA / V^2, Vt = 0.8 V and W/L = 20. The device is operating as a switch for small Vds, utilizing a control voltage Vgs in the range 0 V to 5 V. Find the switch closures resistance, Rds and closure voltage, Vds obtained when Vgs = 5 V and Id = 1 ma. Recalling that Up (Miu)= 0.4 µ(n). What must W/L be for a p-channel device that provides the same...

L W TP MP MC 1 20 10 2 60 40 3 80 4 190 4...

L W TP MP MC 1 20 10 2 60 40 3 80 4 190 4 5 220 What is the wage that this firm must pay for the third worker? _________ What is the wage that this firm must pay for the fifth worker? _________ The TP associated with the first worker is ____________. The TP of three workers is __________. The MC associated with an output of 140 is _______. Diminishing returns sets in with the addition of...

Solve the following dissolution exercises: A. 3 aqueous solutions are mixed: 50 mL of 10% w/v...

Solve the following dissolution exercises: A. 3 aqueous solutions are mixed: 50 mL of 10% w/v HCl, 35 mL of 3.2% w/v NaCl and 65 mL of 13% w/v KCl, which is the final concentration of the solution in %p/v with respect to H +, Na +, K +, Cl- B. What volumes of 8M, 5M and 3M HCl should be mixed to prepare 1 L of 6M HCl C. It is necessary to prepare 35 mL of 15% w/v...

Qd1 Qd2 P Qs1 Qs2 20 40 $10 80 60 30 50 $9 70 50 40...

Qd1 Qd2 P Qs1 Qs2 20 40 $10 80 60 30 50 $9 70 50 40 60 $8 60 40 50 70 $7 50 30 60 80 $6 40 20 18. Which supply and demand combination(s) result in a surplus when the price is $8?_________________ 19. Which supply and demand combination(s) result in a shortage when the price is $8?_________________ 20. Which supply and demand combination(s) result in an equilibrium when the price is $8?_________________

1, Lemonade contains 20% sucrose, 2% salt (NaCl), and 0.5% citric acid (w/v each) in water....

1, Lemonade contains 20% sucrose, 2% salt (NaCl), and 0.5% citric acid (w/v each) in water. Calculate the mole fraction for each of these components (sucrose, salt, citric acid and water). 2. 1000 kg of orange juice containing 15% solids is used to prepare orange juice concentrate in two stages. In the first stage the orange juice is passed through evaporator to remove water. The product from evaporator contains 45% solids. This partially concentrated juice is then fed into a...

PRODUCT 1 PRODUCT 2 Demand 80 80 Time/Unit 30 20 Sale Price 50 30 Variable Cost/Unit...

PRODUCT 1 PRODUCT 2 Demand 80 80 Time/Unit 30 20 Sale Price 50 30 Variable Cost/Unit 10 5 Contribution Margin/Unit 40 25 Contribution Margin Ratio 60% 40% Contribution Margin/Unit of Time 0.33 0.50 Assume the maximum time allowed is only 3,900 per day. Calculate and compare the profitability of the following scenarios: I. The product with the highest contribution margin prioritized. II. The product with the highest contribution margin per unit of constrained resource is prioritized. B How do managers...