Chemistry – Grade 10 Unit 1

Learning Goal Today’s learning goal is for students to: Recall their knowledge of parts of the atom The relationship between atoms and elements Recall what an ion – cation & anion are Recall groups & periods in a periodic table

Review: Parts of the Atom

Review: Parts of the Atom ATOMS are the building blocks of matter – everything is made up of them! Each ATOM is made up of 3 parts Proton (+) Found in the centre of the atom called the nucleus and have a positive charge Electron (-) Small negative charges found around the shell (outside circles) of the atom Neutron (0) Found in the centre of the atom called the nucleus and have NO charge

The Hierarchy of Matter Matter is made up of Elements Elements are made up of ATOMS ATOMS are made up of electrons, neutrons & protons

The Hierarchy of Matter

Closer look at Charges on an Atom Atoms When an atom has the same number of protons and the same number of electrons, then it is a NEUTRAL / No Charge Atom If an atom has more electrons (overall negative charge) or has less electrons (overall positive charge) then the atom is CHARGED When an atom LOSES electrons, it becomes Positively Charged (CATION) When an atom GAINS electrons, it become NEGATIVELY Charges (ANION)

Closer look at Charges on an Atom

Charged atoms create ions Cations are atoms that LOSE electrons and gain positive charge Anions have are atoms that GAIN extra electrons that create a negative charge. 

Checking your learning… What is the difference between an ATOM and an ION? Answer: ATOM – an atom is an electrically neutral particle with an equal number of electrons and protons ION – is an atom that has become charged by gaining or losing electrons.

The Periodic Table

The periodic Table Elements are pure substances that cannot be broken down into simpler substances. The periodic table is a powerful tool that chemists use to explain and predict the properties of the elements There are almost 120 known elements in the periodic table.   The atoms of different elements have different numbers of electrons, protons, and neutrons. Every element is unique and has an atomic number. The Atomic number tells you the number of protons in every atom of the element.

Important Terminology Atomic Number = number of protons and number of electrons in the atom Atomic Mass = sum of the protons and neutrons together Atomic Number = # of protons = # of electrons Atomic Mass = # of protons + # of neutrons Atomic Mass – Atomic Number = # of neutrons

Important Terminology

Chemical Periods and Groups The periodic table also categorizes elements into periods and groups. Each row of elements across in the periodic table is called a period Each column is called a group of elements with similar properties.

Take this time to review with worksheets