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SCIENCE SKILLS 2.1. 2.1 Mass and Volume / Competency B – Lab Skills I can identify and explain how to properly use safety equipment in the science classroom. I can select apparatus and materials for collecting data.
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2.1 Mass and Volume / Competency B – Lab Skills • I can identify and explain how to properly use safety equipment in the science classroom. • I can select apparatus and materials for collecting data. • I can make accurate measurements with appropriate units using lab equipment, including but not limited to graduated cylinder, metric ruler, electronic balance, and displacement tank.
Chapter Two: Science Skills Competency D – Forces and Motion I can explain the differences between mass and weight.
Section 2.1 Learning Goals • Explain the meaning of mass and describe the units for measuring mass. • Distinguish between mass and weight. • Define volume and explain how the volume of matter is measured.
2.1 Measuring mass • Mass describes the amount of matterin an object. • The SI unit for mass is the kilogram (kg). • The kilogram is too large a unit to be convenient for small masses. One gram (g) is one-thousandth of a kilogram. What is the estimated mass of ONE zinc nut?
2.1 Matter • Matter is anything that has mass and takes up space. • All matter has mass. • Steel, plastic, rubber, and glass are different kinds of matter. A car has a lot more of each kind of matter than a bike.
2.1 Mass and weight are different • We tend to use the terms mass and weight interchangeably, but they are not the same thing. • Mass is the amount of matter in an object. • Weight is a measure of the pulling force of gravity on an object.
2.1 Mass and weight are different • A 2.3 kg bag of flour has a mass of 2.3 kilograms no matter where it is in the universe. • The weight of the bag of flour is less on the moon. The 5 lb bag of flour on Earth weighs only .8 lbs on the moon!
2.1 Volume • Volume is the amount of space an object takes up. • The fundamental unit of volume in SI is the cubic meter (m3). • More convenient smaller units are cubic centimeters (cc or cm3), liters (L) and milliliters (mL).
2.1 Volume • Measuring the volume of liquids is easy. • Pour the liquid into a graduated cylinderand read the meniscus at eye level.
2.1 Displacement • You can find the volume of an irregular shape using a technique called displacement. • Put the irregularly shaped object in water and measuring the amount of water displaced.
2.1 Comparing mass and volume • Mass and volume are two different properties of matter. • Size does not always indicate an object’s mass! • How the matter is packed into space is more important.