1 Dimensional Analysis and Measurement Conversions Free Online FlashCards

What is dimensional analysis?

Dimensional analysis, or the factor-label method, converts units by multiplying equivalent fractions so unwanted units cancel.

How should conversion factors be oriented?

Orient each conversion fraction so matching units appear in the numerator and denominator and cancel, leaving the requested unit.

What should you check about units in a conversion?

The remaining unit should match the requested unit. If the units do not cancel correctly, check the setup before calculating.

How many 250 mg tablets equal an order for 0.75 g?

$0.75\,\text{g} \times \frac{1000\,\text{mg}}{1\,\text{g}} \times \frac{1\,\text{tablet}}{250\,\text{mg}} = 3\,\text{tablets}$.

What volume contains 120 mg if the liquid has 160 mg per 5 mL?

$120\,\text{mg} \times \frac{5\,\text{mL}}{160\,\text{mg}} = 3.75\,\text{mL}$. Follow medication instructions and applicable policy for rounding.

When do you multiply or divide in metric conversions?

For metric conversions, multiply when converting to a smaller unit and divide when converting to a larger unit.

How many milligrams are in 1 gram?

$1\,\text{g} = 1000\,\text{mg}$.

How many micrograms are in 1 milligram?

$1\,\text{mg} = 1000\,\text{mcg}$.

How many milliliters are in 1 liter?

$1\,\text{L} = 1000\,\text{mL}$.

Approximately how many pounds equal 1 kilogram?

$1\,\text{kg}$ is approximately $2.2\,\text{lb}$.

What is the common medication equivalent for 1 teaspoon?

Using the common medication equivalent, $1\,\text{tsp}$ is approximately $5\,\text{mL}$.

What is the difference between a fluid ounce and an ounce by weight?

A fluid ounce measures volume; an ounce by weight measures mass. They are not interchangeable.