8th Grade Science Semester Exam 2022

Which scientist discovered electrons?

• Dalton

• Aristotle

• Thomson

Ernest Rutherford and his students did experiments that showed the existence of the...............

• nucleus

• quark

• electron

Tags

NGSS.HS-PS1-8

Bohr proposed that electrons are located in...........

• the electron cloud

• circular orbits around the nucleus

• the nucleus

Which particle is NOT made up of quarks??

• a proton

• a neutron

• an electron

Which type of decay does NOT result in the change of one element into another??

• beta decay

• alpha decay

• gamma decay

Tags

NGSS.HS-PS1-8

An ion forms when an atom gains or loses..........

• protons

• neutrons

• electrons

How are the elements arranged on the periodic table?

• in rows and columns alphabetically

• in one long row according to atomic mass

• in rows and columns according to their properties

Where are metalloids on the periodic table?

• on the left in the table

• in two rows at the bottom

• between metals and nonmetals

The first periodic table arranged elements in order of..........

• increasing atomic mass

• decreasing atomic mass

• increasing atomic number

On most periodic tables, an element's key includes the element's chemical symbol, atomic number, and....................

• density

• atomic mass

• boiling point