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Which pair of properties describes the elements in Group 18?

F They are chemically stable and liquid at room temperature.

G They have eight valence electrons and are flammable

H They are magnetic and boil at low temperatures.

J They are gaseous at room temperature and chemically stable.

Express the following number in scientific notation. 0.026890 =

Compare and contrast physical changes with chemical changes.

Identify one disadvantage to each of the following models of electron configuration: -dot structures -arrow and line diagrams -written electron configurations type in your answer below. (answer) -dot structures do not show the distribution of electrons in orbitals and take up a lot of space. -arrow and line diagrams take up a lot of space and make it difficult to count electrons. -written configurations make it easy to lose count of electrons and do not show the distribution of electrons in orbitals.