Solution strength percentages

Calculators in this field guide use w/w for solution strength percentage. 

Nothing has yet been said about the concentration of polymer required, as it is to be fed to the centrifuge. A level of 0.1% of active ingredient is very common and could be considered the norm. It is more common to quote solution strengths in terms of active ingredient, but polymers, which are supplied in solution or as a dispersion, are sometimes quoted in terms of percentage of as supplied . Care must then be taken when assessing performance. 

FIG. 20-70 The influence of moisture as a percentage of sample saturation S on granule deformabihty. Here, deformation strain (AL/L) is measured as a function of applied stress, with the peak stress and strain denoted by tensile strength and critical strain (AL/L) of the material. Dicalcium phosphate with a 15 wt % binding solution of PVP/PVA Kolhdon VAG4. [Holm et al., Powder Tech., 43, 213 (1.9S.5J,] With land permission from Elsevier Science SA, Lausanne, Switzerland. 

The strength of a solution or emulsion is, of course, corrected by additions of stronger or weaker fluid. The percentage concentration of make-up fluid is calculated by the formula ... 

What is the percentage strength, expressed as % w/w, of a solution prepared by dissolving 60 g of potassium chloride in 150 mL of water ... 

A pharmacist mixes 100 mL of 35% (w/w) hydrochloric acid with enough purified water to make 400 mL. If the specific gravity of hydrochloric acid is 1.20, calculate the percentage strength (w/v) of the final solution. 

What is the percentage strength of a solution containing 20 mEq of potassium chloride per 15 mL ... 

Theory Insulin zinc suspension is nothing but a neutral suspension of insulin in the form of water insoluble complex with ZnCl2. Determination of both total zinc and zinc in solution is performed on a sample of the supernatant liquid obtained by centrifuging the suspension. The percentage of total zinc and of zinc in solution varies according to the strength of the preparation viz., 40, 80 or 100 units ml-1. 

Upon increase in salt concentration to 2 M, histone octamers were obtained (Thomas and Butler, 1978). The octamer could be assembled from acid-extracted as well as from salt-extracted histones (Thomas and Butler, 1978). In a concentrated solution of the four core histones (prepared by acid extraction) at an ionic strength higher than 2 M NaCl (minimum 10 mg/ml histone concentration), there is a small fraction of assembled fibrous structures which can be observed in the electron microscope (Sperling and Bustin, 1976 Wachtel and Sperling, 1979). These fibers (see Fig. 3d) are 60 A in diameter and have a 330 A axial repeat, and were shown to be composed of the four core histones in an equimolar ratio (Wachtel and Sperling, 1979). The percentage of fibers in the solution of the four core histones is promoted by increase in histone and salt concentrations. 

As you should have noticed, percentages are easy to figure out how much reagent to mix with your water. With the formula above and standardized solutions you can also figure the strength in N measurement quite easily. 

The tension or osmotic pressure of a solution also, ionic strength, usually measured as weight percentage. Often the tonicity of a solution is presented as relative to some physiological solution (e.g., blood plasma). See Hypertonic Hypotonic Isotonic Isotonic Buffers... 

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