APPLIED CHEMISTRY IN NURSING (NURS113)

Mr. Luuse Arnold Togiwe

School of Allied Health Sciences, University of Health and Allied Sciences, Ho, Ghana

MeasurementsSI or metric is considered the main system of measurement units used in science today.

Each unit is considered to be dimensionally independent from each other.

These dimensions are described as the measurements of length, mass, time, electric current, temperature, amount of a substance, and luminous intensity.

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Measurements cont’nLength - Meter ( m ):The meter is the SI unit of length..

Mass - Kilogram ( kg ):The kilogram is the SI unit of mass.

Time - Second ( s ):The basic unit of time is the second.

Electric Current - Ampere ( A ):The basic unit of electric current is the ampere.

Temperature - Kelvin ( K ): The kelvin is the unit of thermodynamic temperature.

Measurements cont’n

Amount of a Substance - Mole ( mol ): The mole is defined as the amount of a substance which contains as many entities as there are atoms in 0.012 kilograms of carbon-12.

When the mole unit is used, the entities must be specified. For example, the entities may be atoms, molecules, ions, electrons, cows, houses, or anything else.

Luminous Intensity - candela ( cd ):The unit of luminous intensity, or light, is the candela

Derived unit

A derived unit is a unit that is a combination of base unitskg/m3

m2

m3

m/s m/s2

Conversion factorsName Symbol Factor

Giga G 109

Mega M 106

kilo k 103

Hecto h 102

Deca da 101

Base unit 100

Deci d 10 -1

Centi c 10 -2

Milli m 10 -3

Micro (mc) 10 -6

Nano n 10 -9

Pico p 10 -12

femto f 10 -15

Conversions Calculations

Convert:1. 0.0002kg to grams (g)2. 0.617g to milligrams (mg)3. 0.00021mcg to grams (g)3. 0.006mcg to kilograms (kg)4. 0.015L to mL5. 0.005mcL to mL6. 35000mL to Litres

Conversions Calculations7. 235mm to Centimeters8. 0.617km to meters9. 0.006km to Centimeters10. 13000cm to kilometers

Mass,Volume, Density&Buoyancy

MASSS: Measurement of the amount of matter in an

object– Measured in grams (g)

VolumeMeasurement of the amount of space an object takes up– Measured in milliliters (ml) or cm3

Which do you think would have the greater volume? The greater mass?

Why?

1 kg of feathers 1 kg of rocks

WORK EXAMPLES1.There is an order for 20,000 mg of Ampicillin. Ampicillin is available as 0.021 kg tablets. What should the nurse administer?

ANSWER(Ordered/Have) = Y (Tablets Required)

Convert 0.021 kg to mg.mg ← g ← kg ( x by 1,000 )(0.021 kg x 1,000 x 1,000) = 21,000 mg(20,000 mg/21,000 mg) = 1 tablet

Density is defined as mass per unit volume. It is a measure of how tightly packed and how heavy the molecules are in an object. Density is the amount of matter within a certain volume.

Density

To find the density

3- Divide Density = Mass g Volume c³

1- Find the mass of the object

2- Find the volume of the object

1- Find the mass of the object

ALWAYS REMEMBER UNITS!

some density problems1 Frank has a paper clip. It has a mass of 9g and a volume of 3cm3.

What is its density?

2. Frank also has an eraser. It has a mass of 3g, and a volume of 1cm3. What is its density?

3. Jack has a rock. The rock has a mass of 6g and a volume of 3cm3. What is the density of the rock?

4. Jill has a gel pen. The gel pen has a mass of 8g and a volume of 2cm3. What is the density of the rock?

Atomic Mass Number = (# of Protons) + (# of Neutrons)Example:

A particle with 6 protons and an atomic mass number of 14 has 8 neutrons.

A particle’s name will sometimes include the atomic mass number of the particle.

For example, chlorine-37 is a chlorine atom that has an atomic mass number of 37, meaning that it has a total of 37 protons and neutrons in its nucleus.

Since the atomic number for chlorine is 17, any chlorine atom or ion always has 17 protons. Therefore, a chlorine-37 atom has 20 neutrons, because 37 minus 17 equals 20.

Ions = Charged Particles Ions are formed when atoms gain or lose electrons.

Positive ions (cations) are formed when a neutral atom loses electrons.

Negative ions (anions) are formed when a neutral atom gains electrons.

Metallic atoms tend to lose electrons to form positive ions (cations).

Nonmetallic atoms tend to gain electrons to form negative ions (anions).

Charge = (# of Protons) - (# of Electrons)Example:

A particle with 34 protons and 36 electrons has a charge of -2.