Answer:
I think its iron(II) oxide
Explanation:
The substance is black but when it's mixed with water it turns green solution so when mixed with sodium Hydroxide it turns green
heat is transferred from your hand to the ice cube
Answer:
It is a sample of matter with both constant and definite composition
Explanation:
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
