Download How Do Atoms Combine?

HOW DO ATOMS COMBINE?
ATOMS
• ATOM- THE SMALLEST PARTICLE OF AN
ELEMENT THAT STILL HAS THE
PROPERTIES OF THE ELEMENT.
• THE PROPERTIES OF ATOMS DETERMINE
THE PROPERTIES OF AN ELEMENT AND
HOW THE ELEMENT CAN COMBINE
WITH OTHER ELEMENTS.
PARTS OF AN ATOM
• AN ATOM’S CENTER IS THE NUCLEUS AND CONTAINS:
• PROTONS- HAS A POSITIVE CHARGE
• NEUTRONS- HAS NO ELECTRICAL CHARGE
• AN ATOM IS IDENTIFIED BY ITS NUMBER OF PROTONS.
• THE NUMBER OF PROTONS AND THE ATOMIC NUMBER
ARE EQUAL.
• ELECTRONS- HAS A NEGATIVE CHARGE
• MOVE AROUND THE PROTONS AND NEUTRONS
• IN A STABLE ATOM, THE NUMBER OF PROTONS,
NEUTRONS, AND ELECTRONS ARE EQUAL.
• ELEMENTS ARE ARRANGED BY
THE NUMBER OF PROTONS
(ATOMIC NUMBER)
• LARGER ATOMS ARE ON THE
RIGHT SIDE OF EACH ROW.
• THE COLUMNS ARE ORGANIZED
SO ELEMENTS IN EACH COLUMN
HAVE SIMILAR PROPERTIES
(FAMILIES)
• THE LAST COLUMN ARE CALLED
NOBLE GASES.
• THEY ARE GASES AT ROOM
TEMPERATURE
Each element has an atomic symbol contain 1-3 letters where only the
first letter is capitalized.
• THE DO NOT OFTEN
COMBINE WITH OTHER
ELEMENTS.
MOLECULES
• MOLECULE- THE SMALLEST PARTICLE OF A SUBSTANCE THAT HAS THE
PROPERTIES OF THAT SUBSTANCE.
• THEY ARE MADE OF MORE THAT ONE ATOM AND THEY ARE BONDED TOGETHER
BECAUSE THEY SHARE ONE OR MORE ELECTRONS.
• MANY SUBSTANCES ARE FOUND IN NATURE AS MOLECULES.
• EXAMPLES: AIR IS MADE OF A MIXTURE OF DIFFERENT MOLECULES (OXYGEN,
NITROGEN, AND TRACES OF OTHERS)
• OXYGEN AND NITROGEN MOLECULES ARE MADE OF TWO OF THE SAME
ATOMS BONDED TOGETHER.
COMPOUNDS
• COMPOUND- A TYPE OF MATTER MADE
OF A COMBINATION OF ELEMENTS.
• MOST THINGS YOU SEE AROUND YOU
ARE COMPOUNDS.
• EVERY MOLECULE OF A COMPOUND HAS
THE SAME NUMBER OF ELEMENTS
• A WATER MOLECULE ALWAYS CONTAINS THE
SAME 3 ATOMS, 2 HYDROGEN AND 1
OXYGEN.
Carbon atoms join to form graphite,
which is used in pencils.
PROPERTIES OF COMPOUNDS
• PROPERTIES OF COMPOUNDS ARE DIFFERENT
FROM THE PROPERTIES OF THE ELEMENTS
THAT MAKE THEM UP.
• EXAMPLE: WATER IS A LIQUID AT ROOM
TEMPERATURE, BUT HYDROGEN AND OXYGEN ARE
GASES AT ROOM TEMPERATURE.
• EVERY COMPOUND HAS A NAME AND
FORMULA.
• THE FORMULA SHOWS HOW MANY ATOMS OF
EACH ELEMENT ARE IN THE COMPOUND.
• EXAMPLE: WATER IS MADE OF 2 HYDROGEN
ATOMS AND 1 OXYGEN ATOM, SO THE
FORMULA FOR WATER IS 𝐻2 𝑂
SALTS
• SALTS- COMPOUNDS IN WHICH PARTICLES ARE HELD
TOGETHER BY OPPOSITE CHARGES.
• MAY BE CHARGED ATOMS OR GROUPS OF ATOMS.
• THERE ARE MANY KINDS BUT THEY HAVE SOME
THINGS IN COMMON
• HAVE AT LEAST ONE KIND OF METAL ELEMENT AND ONE KIND
OF NONMETAL ELEMENT
• THEY CAN FORM CRYSTALS
• CRYSTALS ARE FORMED WHEN CHARGED PARTICLES ARRANGE
THEMSELVES IN A REGULAR GEOMETRIC PATTERN.
• HIGH TEMPERATURE ARE NEEDED TO MELT SALTS.
• PROPERTIES OF SALTS ARE DIFFERENT THEN THE
PROPERTIES OF THE ELEMENTS THAT WENT INTO
MAKING THEM.
• EXAMPLE: TABLE SALT IT MADE OF SODIUM AND CHLORINE.
BOTH ARE DANGEROUS TO EAT, BUT WHEN THEY MAKE SALT
YOU CAN EAT IT.