Matter and Scientific Measurement In science we use the SI (Systems International) or METRIC SYSTEM for measurement!

Why do we use the SI (Metric) System?

Length or Distance Length: the distance between two points The TOOLs we use in science are: Metric Ruler, Meter Stick, or Metric Tape. UNITS &SYMBOLS used are: millimeter mm-shorter lengths centimeter cm *meter m - SI standard kilometer km-longer distances

What is MATTER? MATTER is all the substances that make up the universe. All matter has MASS and VOLUME. –ATOMS are the particles that make up all MATTER The ATOM

Two or more ATOMS bonded together make a MOLECULE

H2OH2O A water molecule consists of two Hydrogen atoms bonded to one Oxygen atom (it’s the “Mickey Mouse” molecule)

Everything in the universe is made of atoms/molecules. Molecules can be very complex! This is a molecular model of a supramolecular complex of phenylcarborane with two b-cyclodextrin molecules, a drug being tested to treat brain tumors.

Measuring Weight vs. Mass Objects are slightly lighter when weighed at the equator than at the poles. This is because an object’s weight depends on the force due to GRAVITY. At the equator, gravity is measurably less, so things are lighter. Thus WEIGHT measurements are UNRELIABLE for scientific data.

MASS and VOLUME Mass is the amount of matter(stuff) in an object. Tool Used: Scale or Balance UNITS & SYMBOLS used to measure mass: milligrams mg - very small objects *grams g- Standard SI unit kilograms kg- larger objects –Mass doesn’t change due to GRAVITY! –Therefore we use MASS as a unit of measurement in science!

MASS and VOLUME (continued) VOLUME: is the amount of space taken up by an object –There are different TOOLS & UNITS depending on the state of matter: 1.SOLID 2.LIQUID 3.GAS 4.PLASMA

How do you find the Volume of a SOLID BOX-SHAPED object? The VOLUME of a regular shaped object such as a rectangular box can be found by using: TOOLS - metric ruler, meter stick, or metric tape and multiplying: LENGTH x WIDTH x HEIGHT (or depth) For example: Find the volume of the object below: you would? 3 cm 12 cm

How do you find the Volume of a SOLID BOX-SHAPED object? The VOLUME is found : 12 cm x 3 cm x 3 cm = 108 cm 3 The UNIT is centimeters cubed (cm 3 ) 3 cm 12 cm

How to find the VOLUME of a LIQUID The TOOL used is a GRADUATED CYLINDER. The liquid surface curves downward to form a MENISCUS. To measure accurately, read the scale at eye level at the BOTTOM of the meniscus. Measuring_Volume What is the volume of water in the graduated cylinder?__________ Note: The UNIT is milliliters (ml)

How do you find the Volume of an IRREGULAR shaped object? To find the volume of an irregular shaped object: 1. Fill a container (a graduated cylinder) with enough water to cover the object 2. Measure the INITIALVOLUME of the water 3. Place the object in the water 4. Measure the FINAL VOLUME of the water 5. Find the VOLUME of the OBJECT by the following: Final Volume – Initial Volume = Volume of Object The increase in volume is the volume of the object. This is called the WATER DISPLACEMENT method

How do you find the Volume of an IRREGULAR shaped object? Find the volume of the irregular shaped object:

Final Volume – Initial Volume = Volume of Object 9ml - 7ml = 2 ml = 2 cm 3 Note: The UNIT is cm 3 because the OBJECT measured is a SOLID. For water 1ml = 1g = 1cm 3