The model of the atom has dramatically changed over many many years.We learned atoms make up different substances and are the smallest particles of matter, which have subatomic particles that are very small portions of matter. At first scientist only thought there were electrons which are negatively charged.
A. isotopes only hve different mass which is caused by additional/lesser neutron. protons and electrons number are fixed
Metals are located on the left of the periodic table, and nonmetals are located on the upper right.
Explanation: Metals: Lustrous (shiny)
Good conductors of heat and electricity.
High melting point.
High density (heavy for their size)
Malleable (can be hammered)
Ductile (can be drawn into wires)
Usually solid at room temperature (an exception is mercury)
Opaque as a thin sheet (can't see through metals)
Nonmetals: High ionization energies.
High electronegativities.
Poor thermal conductors.
Poor electrical conductors.
Brittle solids—not malleable or ductile.
Little or no metallic luster.
Gain electrons easily.
Dull, not metallic-shiny, although they may be colorful
It will be B... I hope so. If i am wrong let me know
