First elements
Atoms/periodic table
Matter
Counting atoms
Valence electron
100
Why is hydrogen and helium so special?
Because they are the first elements. Or Because they make up 99.9% of matter.
100
How is the periodic table organized?
By atomic number.
100
What are the 4 types of matter?
Solid, liquid, gas, and plasma
100
How many atoms of hydrogen are in 2C2H6?
12
100
How many valence electrons does calcium have? Atomic number= 20 Atomic mass= 40.078
2
200
Why is helium with the Nobel gases?
Because it has full outer shell.
200
How many groups are on the periodic table?
18
200
What is a homogeneous mixture?
A mixture that has uniform composition and properties throughout.
200
How many oxygen atoms are there in 4K2CO3?
12
200
what is a valence electron?
It is the number on the outer shell.
300
Why is hydrogen by itself?
Because it is its own group and doesn't fit in with any thing else.
300
Who developed the original periodic table?
Mendeleev developed the original periodic table.
300
What makes up a compound?
2 atoms.
300
How many total atoms are in 8Cl2O?
24
300
How do you find the valence electron?
You find the number on the outer shell.
400
How many periods are on the periodic table?
9
400
How total atoms are in 4Fe2O3?
20
400
How many electrons can be on the first shell?
2
500
What is an atom?
An atom is the smallest amount of matter, it can not be cut in half.
500
How many atoms of each element are there in 5Ga2(Cr2O7)3?
Ga=10 Cr=30 O=105
500
How many electrons can be on the 3rd shell?
18
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