Elements, Compounds And Mixtures Flashcards
What is an element
A substance that is made of only one type of atom that cannot be broken down into something simpler by ordinary chemical means
In the periodic table, what is the name for group 1
Alkali Metals
In the periodic table, what is the name for group 2
Alkaline earth metals
In the periodic table, what is the name for group 7
Halogens
In the periodic table, what is the name for group 8
Noble gases
In the periodic table, what is the name for group 8
Noble gases
What does the group number show
Number of electrons in the outermost shells
What does the period number show
number of shells that an atom uses to hold its electrons
What are the characteristics of alkali metals (3)
reactive metals that do not occur freely in nature, but exists in combination with other elements
soft, malleable, ductile, and are good conductors of heat and electricity
react explosively with water, forming an alkali
What are the characteristics of alkaline earth metals (4)
too reactive to be found in nature as an element
harder, less reactive than alkali metals
oxides of these metals form an alkali when dissolved in water
have higher melting points than alkali metals
What are the characteristics for halogens (3)
“halogen” means “salt-former“
when a halogen is combined with a metallic element, it is called a “salt”
halogens can exist in any of the three states of matter at room temp (e.g. chlorine – gas, iodine – solid, bromine – liquid)
What are the characteristics for noble gases (2)
do not combine with other elements readily (i.e. inert).
stable to exist as an element in nature
What are the characteristics for non-metals
do not conduct electricity or heat very well
very brittle, not shiny, and cannot be rolled into wires or pounded into sheets
exist as a solid (e.g. carbon) or a gas (e.g. oxygen)
What is a compound? (2)
A substance that is made of two or more elements (i.e. two or more types of atoms) that are held together by a chemical bond (attraction between atoms)
The chemical properties of a compound are different from those of the individual elements.
e.g. carbon dioxide (CO2) has different properties from carbon and oxygen
What metals form ionic compounds
1 non-metal and 1/more non metal
What metals form molecular compounds
Non metal and non metal
How are ionic bonds held together
By ionic bonds
How are moleculer compounds held together
By covalent bonds
What are the two main methods to attain an octet structure
1.Donating and receiving electrons
2.Sharing electrons
What is the point of an octet structure
To attain a full shell
What happens when forming an ion
the atom loses or gains enough electrons so that its outermost electron shell is fully occupied (i.e. octet structure).
What is a molecule
one particle of a substance made of two or more non-metallic atoms that are held together by a chemical bond
What is a chemical reaction (3)
a process in which one or more substances, the reactants, are converted to one or more different substances, the products.
substances are either elements or compounds
The constituent atoms of the reactants are rearranged to create different substances as products
