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
New Canadian guidelines to prevent and manage obesity in children must focus on family
New guidelines from the Canadian Task Force on Preventive Health...
medicalxpress.com
To stop cancer: Block its messages
The average living cell needs communication skills: It must transmit...
medicalxpress.com
Countdown to Childx: Global health expert Gary Darmstadt on improving newborn survival
Each year, around the world, almost 3 million babies die...
scopeblog.stanford.edu
Newly enlisted T-cell 'policemen' can slow down run-away immune system, scientist says
In research published in the March issue of Immunity, Saint...
medicalxpress.com
Mother's diet influences weight-control neurocircuits in offspring
Maternal diet during pregnancy and lactation may prime offspring for...
medicalxpress.com
Worked-based wellness programs reduce weight, study finds
A new study shows that workplace wellness programs can be...
medicalxpress.com
US Ebola patient's health improves again
An American healthcare worker who contracted the dangerous Ebola virus...
medicalxpress.com
Fat grafting technique improves results of breast augmentation
In women undergoing breast augmentation, a technique using transplantation of...
medicalxpress.com
Percentage of children eating fast food on a given day drops
A lower percentage of children are eating fast food on...
medicalxpress.com
Glyburide associated with more risk of adverse events than insulin in newborns
The medication glyburide, which has been increasingly used to treat...
medicalxpress.com
An apple a day won't keep the doctor away but maybe the pharmacist
Turns out, an apple a day won't keep the doctor...
medicalxpress.com
Team identifies new gene involved in hereditary neuroendocrine tumors
Researchers in the Hereditary Endocrine Cancer Group of the Spanish...
medicalxpress.com
10 Questions: Mary Norine Walsh, MD
(MedPage Today) -- "The waste will continue until the method...
medpagetoday.com
What is the best measure of depression severity in adolescents?
At present the key symptom for diagnosing major depressive disorder...
medicalxpress.com
'Pay-for-performance' may lead to higher risk for robotic prostate surgery patients
A "perverse disincentive" for hospitals that have invested in expensive...
medicalxpress.com
Early stage NSCLC patients with low tumor metabolic activity have longer survival
Low pre-surgery uptake of a labeled glucose analogue, a marker...
medicalxpress.com
Two different fat graft techniques have similar effects on facial skin
Two approaches to fat grafting—injection of fat cells versus fat-derived...
medicalxpress.com
Researchers find new link between neurodegenerative diseases and abnormal immune responses
Researchers from McMaster University and the Icahn School of Medicine...
medicalxpress.com
Family income, parental education related to brain structure in children and adolescents
Characterizing associations between socioeconomic factors and children's brain development, a...
medicalxpress.com
Researchers develop new potential drug for rare leukemia
Researchers at the University of Michigan Comprehensive Cancer Center have...
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 +