Chemistry 1
What are the elements in Group 18 called ?
Noble Gases
How many electrons are in the 3rd energy level?
18
How many sig figs does the following measurement have: 4,007 ml
4
Name all 3 subatomic particles.
Protons Neutrons Electrons
What number do you use to find the number of protons?
atomic number
What are the 3 main states of matter?
Solid, liquid, gas
C-14 has how many neutrons?
8
What is the formula for density?
Density = Mass/Volume (Mass over volume)
How many periods are shown on the periodic table?
7
What is the atomic number of neon (Ne)?
10
What early model of the atom did Thomson develop that involved a lump of positive charge with electrons stuck to it?
Plum-Pudding Model
What is a valence electron?
Electron in the outermost energy level
How are ions formed?
By losing or gaining valence electrons
A negatively charged ion
Anion
The Oxide ion has _____e-
10 e-
The sum of protons and neutrons in the nucleus of an atom is known as the _________
Mass number
When moving from left to right across the periodic table, what increases?
Atomic Number
Where are the electrons in the Quantum model of the atom?
Probably in the energy levels
Elements with the same number of protons but different number of neutrons
Isotope
Will oxygen accept or donate electrons? How many?
Accept two electrons
1 mole of Li has a mass of 7 grams. How many moles are in 21 grams?
3 moles
What is the formula mass of NaCl?
23g + 35g = 58g
3 H2 + 1 N2 = 2 NH3
If 2 mol H2 react with N2, how many moles of NH3
will be formed?
2 mol H2 x 2 mol NH3/3 mol H2 = 1.33 mol NH3
Fluorine, chlorine, bromine, and iodine belong to the family of ______________
halogens
What is the percent composition of H2O?
%-H = 11.11%
%-O = 88.89%
Elements in Group 2A form ions with a charge of ___
+ 2
CS2 has a __________shape according to VSEPR
linear