Measurement Notes Measurement Notes

A.Introduction 1. Most of the world uses the Metric System to measure objects. B. Prefixes This can be abbreviatedS.I. for System International All S.I. units use the following prefixes: a. milli = b. centi = c. deci = d. kilo = milligram =milliliter =millimeter centigram =centiliter =centimeter kilogram =kiloliter =kilometer decigram =deciliter =decimeter MassLiquidLength

2. It’s very easy to use S.I. units because everything is measured in factors of 10 C. Length 1. The S.I. unit of length is theMeter ; it is abbreviatedm 2. AMeter stick or metric ruleris used to measure length. a. One meter is slightly longer than oneyard b. 1 m = 10dm =100cm =1000mm c. 1 km =1000m

d. Volume 1. Volume is the amount ofspaceoccupied by an object. 2. Volume of a regular solid =length xwidth xheight 3. The S.I. unit of volume for solids is the: cubic meter or cubic centimeter ;i t is abbreviated as m³ or cm³ 4. The S.I. unit of volume for liquids is theliter ;it is abbreviatedL a. A liter is slightly larger than aquart b. 1 L =1000mL c. 1 L =1000cm³ d. 1 mL =1cm³ * Gateway conversion factor!!! (it takes you from a liquid unit to a solid unit )

E. Mass 1. Mass is the amount ofmatteran object contains. a. Mass can be measured using abalance. 2. Weight is theeffect of gravityon the mass of an object. a.weightcan change from place to place, but masscannot! 3. The S.I. unit of mass is thegram;it’s abbreviatedg. a. Apaper cliphas a mass of about 1 gram. b. 1 kg =1000g.

F. Density 1. Density is how tightlymass/matteris packed into a certain 2. Density =mass÷volume 3. The S.I. units of density are: g/mL (liquids) or g/cm³ (solids) space/volume.

Conversions Conversions

Memorize the order of the prefixes based on their value/meanings from smallest to largest!! milli centideci unit(m,g,L) deca hecta kilo ,000 To convert from a small unit to a larger unit: move the decimal to the left. To convert from a large unit to a smaller unit: move the decimal to the right. Rules for moving the decimal:

Conversion Factor Method Another method of going from one unit to another involves multiplying by a conversion factor. An Example of a Conversion factor: 60 seconds = 1 minute. We write conversion factors like: 60 sec or 1 min 1 min 60 sec

Example: How many seconds are equal to or are in 1 year? Solution: Use the following steps: 1. Start with the original number and unit. 2. Multiply by a conversion factor with the unit to be discarded(cancelled out) on the bottom and the desired unit on the top. Bring in as many conversion factors as it takes to get to the desired final unit. (Originally we were in one year, but our desired final unit is seconds) 3. Cancel units. 4. Perform mathematical calculations. 1 year x 365days x 1yr 24hrs x 1day 60min x 1hr 60sec = 1min 31,536,000sec = 1 31,536,000sec This problem was completed using conversion factors we had memorized…how do we solve problems with conversion factors we don’t have memorized? It’s easy…use the chart or a reference!!!!

Metric Conversion Chart m(m, L, g) c(m, L, g) d(m, L, g) m, L, g da(m, L, g) h(m, L, g) k(m, L, g) 1m(m, L,g)= c(m, L, g)= d(m, L, g)= m, L, g = da(m, L, g)=10, h(m, L, g)= 100,000 10, k(m, L, g)= 1,000, ,000 10,

Memorize the following “Gateway” Conversion Factors: 1 in.__ 2.54cm or 2.54cm 1in  for going from a unit in Standard to a unit in Metric 1 mL 1 cm³ Or 1cm³ 1 mL  for going from a liquid unit to a solid unit

Using the conversion factor method: Convert 50L into cm³

Using the conversion factor method: Convert 850ft to cm

Using the conversion factor method: Convert 150g/L to hg/mL