Transcript Slide 1
Atoms Goal of the class • To introduce matter and discuss how it can be classified and what it’s made up of. • Question of the day: What are the three main components of atoms? Atoms • All matter is made of atoms – Atoms are the smallest units of matter with unique properties – Atoms are made of three different types subatomic particles: protons, electrons, and neutrons Atomic Size • Atoms are about 100 picometers (10-10 meters) – Too small to reflect visible light (no color) – Can only be seen with an electron microscope • If an atom was the size of an orange, then an orange would be the size of the earth. Atomic Size World’s Smallest Movie http://www.ibm.com/madewithatoms Atomic Mass • The subatomic particles within an atom have the following masses: Proton Neutron Electron 1 1 1/2000 • Electrons have much less mass than protons or neutrons. Atomic Composition • Atoms are made up of a nucleus and the electron cloud around it – Atoms are mostly empty space – The nucleus is very small, has all protons and neutrons – Electrons occupy specific regions of the electron cloud Electromagnetic Force • The different parts have different electromagnetic charge – The charge of electrons act similar to magnets – Opposite charges attract while like charges repel each other. • Protons have a positive charge • Electrons have a negative charge • Neutrons have no charge Atom Charges • If an atom has more protons than electrons it will have a positive charge • If an atom has less protons than electrons it will have a negative charge. • If the number of electrons and protons are the same the atom is neutral. Matter’s Properties • An atom’s properties will be determined by the number of subatomic particles – Example: The number of protons and neutrons will determine the mass of an atom – The number of protons and electrons will determine reactivity, or cohesion New Seating Plan Projector Peter Eric Kim Chris Brian Mark Hareem Sophia Alex Daniel Ha Joseph Gloria Jiin Eric Kang Miguel Phillip Danny Jun Ryan Vocabulary • Subatomic – relating to particles smaller than atoms (electron, neutron, proton). • Electromagnetic – a fundamental force that is a combination of electrical and magnetic forces • Neutral – Atoms that contain the same number of protons as electrons Homework • Please read Chemical Building Blocks pages 76-77 • Please complete Chemical Building Blocks workbook page 33-34 • Play with http://phet.colorado.edu/en/simulation/ build-an-atom