Quantcast Weight/Volume Percent Solutions - Laboratory Mathematics

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Custom Search
 
  
 
percentage, which means parts per 100 total parts. This method is used with all three
of the basic comparisons of percent concentration statements, that is, weight/weight,
weight/volume, and volume/volume. The percent weight/weight is not commonly used
in the clinical laboratory.
2-27. WEIGHT/VOLUME PERCENT SOLUTIONS
a. The weight per unit volume system of percent concentration is the most
frequently used method in the clinical laboratory. This method is used when a solid
solute is mixed with a liquid solvent. Since percent is parts per 100 parts of total
solution, then a weight/volume percent solutions (w/v) unit would be grams of solute per
100 milliliters of total solution (g/100 mL). In the clinical laboratory and related
situations, any time a w/v solution is described by a number followed by a percent
symbol (grams per 100 mL (g/100 mL). Since 100 milliliters is equal to one deciliter,
then a percent w/v concentration can be expressed as grams per deciliter (g/dL).
b. Another expression of w/v percent concentration used in the laboratory
involves the use of fractional parts of the gram while retaining the unit of volume of
solution. Examples of this kind would be milligram per deciliter or milligram percent.
These may be expressed as mg/dL, mg/100 mL, or mg
c. The following problems may be solved using dimensional analysis (see
Appendix A); however, simple ratio and proportion will suffice in some instances. Both
methods of problem solving will yield comparable results.
d. Example. If a 5.0 g/dL solution of NaCl is to be prepared with a volume of
50 mL, how much NaCl would be required?
Solution. Based on definition the same problem could be solved using
appropriate factors.
By dimensional analysis, we would solve as follows:
After reading the problem carefully it should be quite evident that the desired
quantity is the amount of solute expressed in grams.
Express the volume in dL
1 dL
50. 0 mL X = -------- = 0.500 dL
100 mL
Multiply the volume expressed in deciliters times the percent concentration to
determine the amount of solute contained in the specified amount of total solution.
5.0 g
0.500 dL X = ------ = 2.5 g
dL
MD0837
2-8



Medical News
Congenital heart disease specialists develop nonsurgical technique to correct birth defects
A new technique for repairing the most common cardiac birth...
medicalxpress.com
Health Care Funding Changes Impact STI Testing, Study Finds
Universal health coverage and changes in the way Massachusetts funds...
bumc.bu.edu
Preterm children's brains can catch up years later
There's some good news for parents of preterm babies –...
medicalxpress.com
West African airline suspends flights amid Ebola
(AP)—The West African airline that transported a passenger sick with...
medicalxpress.com
Mortality rates increase due to extreme heat and cold
Epidemiological studies have repeatedly shown that death rates rise in...
medicalxpress.com
Women who smoke while pregnant could alter their children's genes
The largest study of its kind has shown that smoking...
medicalxpress.com
Herpes remains active even when no symptoms appear
Scientists investigating the herpes virus have been surprised to find...
medicalxpress.com
Morning Break: Medicare's Sell-By Date Extended
(MedPage Today) -- Health news and commentary from around the...
medpagetoday.com
Determine patient preferences by means of conjoint analysis
The Conjoint Analysis (CA) method is in principle suitable to...
medicalxpress.com
Researchers explore what happens when heart cells fail
Through a grant from the United States-Israel Binational Science Foundation,...
medicalxpress.com
New anesthesia technique helps show cause of obstruction in sleep apnea
A simplified anesthesia procedure may enable more widespread use of...
medicalxpress.com
Key element of CPR missing from guidelines
Removing the head tilt/chin lift component of rescue breaths from...
medicalxpress.com
New research describes trends in substance use among high school athletes
Newly published research from Journal of Child & Adolescent Substance...
medicalxpress.com
What is the plague?
Cases of plague have been reported in the Chinese city...
medicalxpress.com
Low-carb diet recommended for diabetics
A new study involving researchers from the University of Alabama...
medicalxpress.com
It takes more than practice to excel, psychologist reports
Case Western Reserve University's new assistant professor of psychology Brooke...
medicalxpress.com
Collaborative study of uninsured smokers finds benefit from pairing nicotine patches with quitline support
Uninsured smokers who used nicotine replacement therapy (NRT) patches in...
medicalxpress.com
Asbestos Revisited: A New Autoimmune Disease? (CME/CE)
(MedPage Today) -- In the small town of Libby in...
medpagetoday.com
Elderly can get fit in 60 seconds
The health of OAPs can be dramatically improved with high-intensity...
medicalxpress.com
Over 70 and still driving, who do you listen to?
Studies show older drivers self-regulate their actions behind the wheel,...
medicalxpress.com
 


Privacy Statement - Copyright Information. - Contact Us

comments powered by Disqus

Integrated Publishing, Inc.
9438 US Hwy 19N #311 Port Richey, FL 34668

Phone For Parts Inquiries: (727) 755-3260
Google +