Answer:
(2) Student A scored 15 points higher than student B
Explanation:
Because they said 15 points higher instead of their grades are better (The same thing 4 does.
If a metal is less reactive than carbon, it can be extracted from its oxide by heating with carbon. The carbon displaces the metal from the compound, and removes the oxygen from the oxide. This leaves the metal.
How to Tell Lewis Diagrams apart
Trigonal planar, Trigonal pyramid both have 3 things attached to them. Not 4. Tetrahedral is the only Lewis Diagram's center piece that has 4 things attached to it.
<em><u>Tetrahedral</u></em>: C with 4 Cl's attached.
<em><u>Trigonal Planar</u></em>: is flat. The element in the middle is generally a metal or an element from the Left side of the periodic table. There is never an isolated pair of electrons with Trigonal Planer shapes. Summary:
- The center element is a Metal on the left side of the periodic table.
- In your example, Boron is at the center of the drawing and it is in column 2 of the periodic table which makes it a metal.
- There are no isolated electron pairs
Trigonal Pyramid
- The two electrons are circled. These two are isolated and nothing is attacted to them.
- The central element is a non metal -- Nitrogen in this case.
- The non metal is on the RIGHT side of the periodic table
Bent
- Looks like it is in a straight line (but it is not).
- There are usually double bonds involved.
- The angle formed is usually greater than 90 degrees
- The central element is usually a non metal.
Problem One
Both parts of this question are correct.