Answer:
Retrograde Motion
Explanation:
Geocentric model of planets was proposed by Ptolemy. It stated that all sun, planets and stars revolve round the earth in circular orbits.
NOTE: Ptolemy: an ancient astronomer, geographer, and mathematician who considered the Earth the center of the universe (the "Ptolemaic system").
EASY AS PIE AND I LIKE PIE
Calcium iodide (CaI2) is an ionic bond, which means that electrons are transferred. In order for Ca to become the ion Ca2+, the calcium atom must lose 2 electrons. (Electrons have a negative charge, so when an atom loses 2 electrons, its ion becomes more positive.) In order for I to become the ion I1−, the iodine atom must gain 1 electron. (When an atom gains an electron, its ion will be more negative.) However, the formula for calcium iodide is CaI2 - there are 2 iodine ions present. This makes sense because the iodine ion has a charge of -1, so two iodine ions have to be present to cancel out the +2 charge of the calcium ion. Therefore, the calcium atom transfers 2 valence electrons, one to each iodine atom, to form the ionic bond.
IF WRONG, SORRY
Answer:
The purpose of molecular modeling is to provide a three-dimensional image (either physical or software-based) that allows a chemist to better see the manner in which atoms and molecules can interact. These models can be used to interpret existing observations or to predict new chemical behavior.
Explanation:
It can describe shape and how they connect while forming the electrons.
Answer:
To tell if something is an acid or a base, you can use a chemical called an indicator. An indicator changes color when it encounters an acid or base. There are many different types of indicators, some that are liquids and others that are concentrated on little strips of "litmus" paper.
Explanation: