science Atomic Structure test

Who is given credit for the creation of the periodic table?

Dmitri Mendeleev

What is a group/family?

the vertical columns (up and down)

What do elements in the same group/family have in common?

valence electrons

What is a period?

the horizontal rows (side to side)

What do elements in the same period have in common?

electron shell

What does Periodic Law state?

"When elements are arranged in order of increasing atomic number, there is a periodic repetition of their chemical and physical properties.

How many valence electrons does calcium have?

2 valence electrons

How many energy levels does strontium have?

5 energy levels

What is a metalloid?

chemical elements whose physical and chemical properties fall in between the metal and non-metal categories

What does average atomic mass tell us about an element?

measured in atomic mass unit

What does atomic number tell us about an element?

the number of protons in the nucleus of an atom.

Where are metals located on the periodic table?

bottom left (Groups 1, 2, and 13–15)

What are some characteristics of metals?

good conductors of heat and electricity

Where are non-metals located on the periodic table?

top right (except hydrogen)

What are some characteristics of non-metals?

poor conductors of heat and electricity

Describe the size of a proton, neutron, and electron.

Electrons are much smaller than protons or neutrons

Where are protons located?

the nucleus

What kind of charge do protons have?

positive charge

Where are neutrons located?

inside the nucleus of every atom

What charge do neutrons have?

neutral charge

Where are electrons located?

outside the nucleus

What charge do electrons have?

negative charge

What overall charge does an unreacted atom have? Why?

Atom have no electric charge because the positive charges equal the negative charges

Who was the first person to say that the atom was the smallest indivisible unit of matter and was like a small, dense ball?

Democritus

What famous experiment did Rutherford use to discover the nucleus of the atom?

gold foil experiment

What did JJ Thompson relate his model of the atom to?

plum pudding

Who created the modern day, 2-D view of the atom that we still use today

John Dalton

What is an isotope?

Atoms with the same number of protons but different numbers of neutrons

Where is the majority of the atom’s mass?

nucleus

Do electrons contribute to the atomic mass of an atom?

they do not contribute to the mass of the atom.

What is the maximum number of electrons that the 1 st energy level can hold?

2 electrons

What is the maximum number of electrons that the 2nd energy level can hold?

8 electrons

What is the maximum number of electrons that the 3 rd energy level can hold?

18 electrons

What is the average atomic mass for all of the isotopes of neon?

20\.18

What is the only liquid metal on the periodic table?

Mercury