Structure of an Atom
Which subatomic particle IDENTIFIES an atom?
Protons (because every element has a different number of protons)
What determines an element's chemical properties, including reactivity?
It's number of valence electrons
The small, dense center of the atom
Nucleus
A chemical change is a process in which atoms are ______________ to produce a new substance. (jp 19)
rearranged
A scientist is studying an unidentified element. It is a metal with 2 valence electrons and 5 electron shells/rings. What element is it?
Strontium (Group 2, Period 5)
Name what two things protons and neutrons have in common. BE SPECIFIC!
Location in the nucleus and a mass of 1 amu
Group 1 likes to bond with group 17. Why is group 1 so reactive?
They only have one valence electron
The LARGE number in front of a chemical formula that tells you how many MOLECULES you have of that substance
Coefficient
A ______________ is two or more different elements joined together (jp 21)
Compound
How many TOTAL atoms are in this formula?
H3Be2SC5Si
12
If an atom has 3 protons, 4 neutrons, and 3 electrons, then what is the overall charge of the atom?
Neutral or 0 (the positive protons and negative electrons cancel each other out)
Is Bromine (Br) a metal, nonmetal, or metalloid?
Nonmetal (right of the zig-zag line)
The SMALL number that comes behind an element; tells you how many ATOMS you have of that element
Subscript
Valence electrons are the electrons on the ________________ shell or ring. (jp 13)
Outermost
Which element is named after the 7th planet from the sun?
Uranium
If an element has 55 protons, 55 electrons, and an atomic mass of 133, then how many neutrons does it have?
78 neutrons (133 - 55 = 78)
What is the only metalloid in period 2?
Boron
PRODUCTS
Elements are most similar to other elements in their _______________. (jp 13)
Group
What is the most abundant element in the universe?
Hydrogen
How many protons, neutrons, and electrons are in an atom of arsenic (As) with a mass number of 75? (Write out the number of all 3 particles)
P = 33, N= 42, E = 33
(APE: 33, MAN: 75-33=42)
How many valence electrons does an atom of Iodine contain?
7 valence electrons (because its in group 7A)
The elements that are typically good conductors, malleable, and shiny; LEFT of the bold zigzag line in the periodic table
Metals
Signs of a chemical reaction include production of gas/bubbles, an odor, a precipitate, and a change in temperature or a change in ___________. (jp 19/20)
color
A penny (the coin worth 1 cent) is made of which two elements?
Copper and Zinc