Determine Concentration and Molarity

Determine Concentration and Molarity Molarity is one of the most common and important units of concentration used in chemistry. This concentration problem illustrates how to find the molarity of a solution if you know how much solute and solvent are present. Concentration and Molarity Example Problem Determine the molarity of a solution made by dissolving 20.0 g of NaOH in sufficient water to yield a 482 cm3 solution. How to Solve the Problem Molarity is an expression of the moles of solute (NaOH) per liter of solution (water). To work this problem, you need to be able to calculate the number of moles of sodium hydroxide (NaOH) and be able to convert cubic centimeters of a solution into liters. You can refer to the Worked Unit Conversions if you need more help. Step 1 Calculate the number of moles of NaOH that are in 20.0 grams. Look up the atomic masses for the elements in NaOH from the Periodic Table. The atomic masses are found to be: Na is 23.0H is 1.0O is 16.0 Plugging these values: 1 mol NaOH weighs 23.0 g 16.0 g 1.0 g 40.0 g So the number of moles in 20.0 g is: moles NaOH 20.0 g Ãâ€" 1 mol/40.0 g 0.500 mol Step 2 Determine the volume of solution in liters. 1 liter is 1000 cm3, so the volume of solution is: liters solution 482 cm3 Ãâ€" 1 liter/1000 cm3 0.482 liter Step 3 Determine the molarity of the solution. Simply divide the number of moles by the volume of solution to get the molarity: molarity 0.500 mol / 0.482 litermolarity 1.04 mol/liter 1.04 M Answer The molarity of a solution made by dissolving 20.0 g of NaOH to make a 482 cm3 solution is 1.04 M Tips for Solving Concentration Problems In this example, the solute (sodium hydroxide) and solvent (water) were identified. You may not always be told which chemical is the solute and which is the solvent. Often the solute is a solid, while the solvent is a liquid. Its also possible to make up solutions of gases and solids or of liquid solutes in liquid solvents.  In general, the solute is the chemical (or chemicals) present in smaller amounts. The solvent makes up most of the solution.  Molarity is concerned with the total volume of the solution, not the volume of the solvent. You can approximate molarity by dividing moles of solute by volume of solvent that is added, but this isnt correct and can lead to significant error when a large amount of solute is present.Significant figures can also come into play when reporting concentration in molarity. There will be a degree of uncertainty in the mass measurement of the solute. An analytical balance will yield a more precise measurement than weighing on a kitchen scale, fo r example. The glassware used to measure the volume of solvent also matters. A volumetric flask or graduated cylinder will yield a more precise value than a beaker, for example. Theres also an error in reading the volume, relating to the meniscus of the liquid. The number of significant digits in your molarity is only as many as that in your least precise measurement.

Healthcare Worker Shortage Leads Some Hospitals to Take Extra Steps

Healthcare Worker Shortage Leads Some Hospitals to Take Extra Steps There is currently  a shortage of U.S. health care personnel, and  it is only likely to get worse. According to a study by the U.S. Health Resources and Services Administration, within the next 10 or 15 years, 1 million nurses are expected to retire. Additionally,  the number of practicing physicians is expecting a shortfall of 55,000 by 2020. The aging population will have a large impact on the number of nurse jobs and other health-related positions sorely needed to keep facilities running.A large number of students require additional background coursework in order to take credited health care courses, which deters people from pursing health care careers. Often, these additional  courses are in more difficult areas of study, such as mathematics or chemistry. Instead of tackling them, students are switching career paths.Alternatives to Community CollegeSome hospitals are offering in-house training programs to ensure that appropriate staffing will continue. In Michigan, one pr ogram allows employees to work while training to obtain medical assistant jobs. Upon completion, the employee will be licensed and credentialed, a bonus for the hospital employer and a practical way for an employee interested in the health care field to gain knowledge.Hospital StrategiesMany hospitals realize that happy employees are more likely to stay on the job and may work past retirement age. Some offer in-house training programs, and others offer tuition reimbursement as incentive to continue toward a degree or licensure.Because of the anticipation of a continued shortage, some hospitals have found that pairing an entry level employee with a seasoned   one helps keep the older employee up on the latest technologies in the field, while the younger employee has the benefit of the other’s years of expertise.Hospital and Community College CooperationIn some areas, such as the San Francisco Bay area, hospitals have been working in conjunction with community colleges to off er training and additional support for nursing staff. By combining classes and residency experience at one time, trainees feel more confident, and the retention rate is higher.In addition, it gives the hospital the opportunity to train nursing students in needed positions, such as surgical assistants in the operating room. Other employees who are not taking nursing classes are offered tuition reimbursement, and the hospital continues to pay their salary while they attend school if the individual expresses an interest in furthering their career in health care.If you are looking for a job in health care, turning to TheJobNetwork makes your search simple. Sign up for free with this online platform and enter the type of job you want. The platform lets you specify criteria you are looking for in the job as well as letting you enter your qualifications and a resume. You can actively search for a job or let the platform do the search for you. You’ll receive an email when jobs are fo und. All you have to do is apply.