Matter 2
What happens when matter is heated.
The particles expand
What’s an ion?
an atom that loses or gains an electron
Which group number are the halogens?
Group 17
What is the octet rule?
Where the atom wants 8 valence electrons
What is the strongest of the three IMFS?
Hydrogen Bonding
What is the difference between physical and chemical changes
A physical change alters the way it looks but doesn’t change any molecules while a chemical change changes the molecules.
What causes molecules to repel or attract.
Electrostatic forces
As you move up a group, what happens to an atom’s atomic radius?
It decreases in size
What does a high IE indicate about an atom?
The atom has a very strong hold over its electrons, or it is unwilling to share
How many valence electrons do Halogens have?
7
List two ways to separate mixtures
Filtration, Evaporation, and Magnetic
Why did some particles get deflected in the gold foil experiment?
Like charges repel and because Alpha particles are also positive, the now-proven positive nucleus reflects the alpha particles.
Why does the attraction between valence electrons and the nucleus decrease as you move down a period on the periodic table?
The atomic radius increases as more energy levels are added and the ve- receive greater shielding from inner e-, decreasing the attraction.
Between what values are polar covalent bonds?
0.4 – 1.7
What is the difference between trigonal planar and trigonal pyramidal?
Trigonal planar has one lone pair, trigonal pyramidal has none
OR
Trigonal planar is a 2d flat shape, while trigonal pyramidal is a 3d pyramid.
Explain what happens to elements after they turn into a compound.
The elements that are in the compound are no longer the same as the elements they originally were. They basically lose all their original properties.
How many unpaired electrons does gallium have
1
When moving across a period, why does the atomic radius of an atom decrease?
The atoms within the same period occupy the same principle energy level but their nuclear charge increases, causing the attraction between the nucleus and ve- to increase.
What element(s) follow the duet rule?
Hydrogen and Helium
Draw Lewis structure for BeF2 with the dipoles.
Emma will do it for you
Explain the dual nature of the electron
An electron can act as both a particle and wave at the same time.
Explain how shielding works
Shielding works when inner core electrons block the attractive force of the nucleus from reaching the outer valence electrons
Metals tend to have less electronegativity than nonmetals. What does this suggest about their IE when compared to nonmetals?
Due to the trend of IE increasing as you move left to right, metals will have less IE than nonmetals as they are to the left of the periodic table while the nonmetals are on the right.
Draw a lewis structure for SiBr4
Emma will draw it for you
Draw the Lewis structure for carbon tetrahydride and identify it's molecular geometry.
Emma will do this for you