Question | Answer |
What did Mendeleev recognize? | When the elements were arranged in order of increasing atomic mass certain similarities in their chemical properties appeared at regular intervals |
Who made the first periodic table? | Mendeleev |
What led Mendeleev to leave blank spaces on his periodic table? | he predicted the existence and properties of the elements that he believed would fill the spaces. |
What was wrong with Mendeleev's table? | Most of the elements could be arranged in order of increasing atomic mass but a few could not. |
What did Moseley discover about atomic structure? | that the atomic number is the basis for the organization on the periodic table |
How did Moseley arrange his periodic table? | by increasing number of protons in the neclues |
What is periodic law? | The physical and chemical properties of the elements are periodic functions of their atomic numbers |
Is the periodic law based upon Mendeleev's or Moseley's PT? | Moseley |
Is the modern PT from Moseley or Mendeleev? | Moseley |
Representative elements include group numbers | 1-8 |
Transition elements include | the middle section |
Inner Transition elements include | the bottom two rows |
What are the three main catagories of elements? | metals,nonmetals, and metalloids |
The ability of a substance to be hammered into sheets | malleable |
The ability of a substance to be drawn out into wire | ductile |
material which permits the flow of energy | conductor |
Break or shatter easily | brittle |
Why do elements in the same group have similar chemical properties? | they have the same number of electrons |
Where are the s block elements located? | groups 1-2 (the left side) |
Where are the p block elements located? | groups 13-18 (the right side) |
Where are the d block elements located? | groups 3-12 (the middle section) |
Where are the f block elements located? | bottom 2 |
What arrangement of electrons is particularly stable? | having a full outer energy lever (also called an octet) |
How many naturally occurring elements? | 92, 93+ are man-made |
Metals are ... | left of zigzag on PT
shiny
solid at room tempurature
conduct heat/electricity
malleable
ductile
react with some acids to form hydrogen gas |
All metals are solid except | mercury |
Nonmetals are ... | right of zigzag
generally gasses or brittle at room temp
poor conductors |
Nonmetals are generally gasses or brittle at room temp except | bromine |
Metalloids are ... | along the zigzag
properties of both metals and nonmetals |
Group I of the PT is also known as the | alkali metals/ sodium family |
Group I of the PT properties are | extremely chemically reactive
one valance electron
e- conf. always ends in s^1
developed charge +1 in chem. rx. |
Group II of the PT is also known as | alkaline earth metals/ calcium family |
Properties of Group II on the PT are | chemically reactive
two valance electrons
e- conf. always ends in +2
develop a charge of +2 in chem. rx. |
Group III on the PT also known as | boron family |
Properties of Group III on the PT are | moderately chemically reactive
three valance electrons
e- conf. always ends in s^2 p^1
develop a charge of +3 in chem. rx. |
Group IV on the PT is also known as | carbon family |
Properties of Group IV are | somewhat chemically reactive
4 valence electrons
e- conf. ends in s^2 p^2
develop charge of + or - 4 in a chemical reaction |