Let’s look at the chart again. Meter, Liter, GramStandard Unit SI

Let’s look at the chart again.

Kilo EXAMPLE: 1000m = 1 km 1000 L = 1 kL 1000g = 1kg

Let’s look at the chart again.

Centi 100 cm = 1m 100 cg = 1 g 100 cL = 1 L

Let’s look at the chart again.

milli 1000 mL = 1L 1000 mg = 1g 1000 mm = 1m

EX. How many meter are in 925 km? 925 km? m=

Do the Math 925 kmx km m 1 1,000 1 x 1 = 925 x 1,000 1 = 925,000 =

LecturePLUS Timberlake11 Solution Unit plan: days hr min seconds 1.4 day x 24 hr x 60 min x 60 sec 1 day 1 hr 1 min = 1.2 x 10 5 sec

Accuracy versus Precision Accuracy: how close you are to the actual value Precision: the ability to measure with exactness, repeatability.

Accuracy versus Precision VALUES IN DATA: cm cm cm cm ACTUAL VALUE: 99 cm The data is precise, but not accurate

Accuracy versus Precision VALUES IN DATA: cm cm cm 99.2 cm ACTUAL VALUE: 99 cm The data is accurate but not precise

Accuracy versus Precision VALUES OF DATA: cm cm cm cm ACTUAL VALUE: 99 cm The data neither accurate nor precise

Accuracy versus Precision VALUES OF DATA: cm cm cm cm ACTUAL VALUE: 99 cm The data is both accurate and precise.

CALCULATING DEGREE OF ERROR Measurement – Actual Value X 100 Actual Value EX: measurement is 29. Actual Value is – 27.5 X 100 = 5.45% percentage of error 27.5

OTHER MEASUREMENTS VOLUME = L, cm 3, cc MASS= g LENGTH= m DENSITY = g/ml, g/cm 3

LET’S REVIEW

The safest way to dilute concentrated sulfuric acid is to add: – A series of small volumes of water to the acid while stirring. – The acid to water slowly while stirring constantly. – The acid to a small volume of water and then add more water. – Dilute sulfuric acid to a small volume of the concentrated acid.

Intensive versus Extensive Intensive – Molecule Activity Extensive – Amount of matter

WHAT HAPPENED TO THE DENSITY OF THE SUBSTANCE???

What is the most appropriate unit of measure for reporting the density of a solid? – g/cm 3 – g/cm – g/L 2 – g/mm 2

Volume is space the matter takes up

cm 3 = cc = mL These are the measurements of volume. The METRIC measurement for VOLUME is mL There will be at least three questions when you will need to know this.

Which of the following pieces of equipment would be most appropriate for measuring the volume of a marble?

How many significant figures , ,057

What do these PREFIXES mean Kilo Centi Milli

KILO Greek for ‘thousand’ Means 1000 times larger

Centi Latin for ‘hundred’ Mean 100 times SMALLER

milli Latin for ‘thousand’ Means 1000 times smaller

Temperature Conversions K o = C o C o = K o F o = 9/5 (C o +32) C o = 5/9 (F o -32) WHAT YOU’RE GIVEN ON THE STAAR EXAM AND TAKS 0 C o = 273 K o

Precision and Accuracy Team cm Team cm Team cm Team cm ACTUAL MEASUREMENT Team cm 2.70 cm Team cm Accurate, precise, both or neither

Percentage of Error Measurement – actual value X 100 = % actual measurement EXAMPLE: team – 2.70 X 100 = 1.85 % 2.70

The quantitative measurement among the following is: – The girl is taller than the boy. – The girl is tall for her age. – The girl is the tallest in the class. – The girl is 7 feet tall.