4.1.2 The periodic table Flashcards
How are the elements in the periodic table arranged?
By increasing atomic (proton) number and so that elements with similar properties are in groups.
Q: Why is it called the periodic table?
Because similar properties occur at regular intervals.
Q: What do elements in the same group have in common?
A: They have the same number of electrons in their outer shell, giving them similar chemical properties.
Q: How does the position of an element in the periodic table relate to its electron arrangement?
A: The group number corresponds to the number of outer electrons, and the period indicates the number of shells.
Q: How can the periodic table predict reactivity?
A: By identifying the group and period, which relate to outer electron configurations.
Q: Why were early periodic tables incomplete?
A: Some elements were placed in inappropriate groups if strict atomic weight order was followed.
Q: How were elements initially classified?
A: By arranging them in order of atomic weights.
Q: How did Mendeleev address the limitations of early periodic tables?
A: He left gaps for undiscovered elements and reordered some elements based on properties.
Q: What confirmed Mendeleev’s predictions?
A: Discovery of elements that matched his predicted properties.
Q: How did the discovery of isotopes improve the periodic table?
A: It explained why atomic weight order sometimes disagreed with chemical properties.
Q: What type of ions do metals form?
A: Positive ions.
Q: Where are metals and non-metals located in the periodic table?
A: Metals are to the left and bottom; non-metals are to the right and top.
Q: How do the properties of metals and non-metals differ?
A: Metals are conductive, malleable, and form basic oxides, while non-metals are insulative, brittle, and form acidic oxides.
Q: How does atomic structure explain these properties?
A: Metals have delocalized electrons, while non-metals have more tightly held electrons in their outer shells.
