Science 9

What is the term for the outermost electrons in an atom that are involved in chemical bonding?

• Protons

• electrons

• Neutrons

• Valence electrons

what is the chemical symbol of gold?

• Ag

• Au

• Ca

• Mg

Which of the following characteristics are typically associated with metals?

• Brittle and non- conductive

• low melting point and low density

• Malleable and ductile

• Insoluble in water and gas at room temeperature

what is the chemical formula for salt?

• NaCO3

• Nacl

• NaOH

• NA2O

what is the atomic number of Nitrogen, considering that it is makes up about 78% of Earth's atmosphere and has 7 protons and electrons ?

• 5

• 7

• 17

• 8

When Be, a metal with 2 valencce electrons, lose 2 electrons, what is the resulting chemical formula

• Be-

• Be2+

• Be

• Be+

what is chemical fomula of glucose?

• C6H12O6

• C12H22011

• NaCl

• NaHCO3

How is the arrangement of valence electrons in the periodic table?

• by column

• by line

• by period

• by row

what is the maximum number of electronss in the third energy level?

• 6

• 18

• 32

• 8

Who presented an atomic model with electrons in fixed orbits around the nucleus?

• Erwin Schrodinger

• J.J. Thomson

• Neils Bohr

• Werner Heienberg