Answer:
Kinetic energy is the energy that an object has because of its motion. The molecules in a substance have a range of kinetic energies because they don't all move at the same speed. As a substance absorbs heat the particles move faster so the average kinetic energy and therefore the temperature increases.
The polarity of a water molecule
comes from the uneven distribution of electron density of hydrogen and oxygen
atom. The oxygen in the water molecule is more electronegative than the
hydrogen. Water has a partial positive charge near the hydrogen atom and a
partial negative charge near the oxygen atom. The result of this
electrostatic attraction results in the bond called hydrogen bond. Also,
because of this bond, it has the ability to dissolve most of the solutes due to
its polarity and bonding.
Potassium oxide: K₂O.
There's no need for prefixes since K₂O is an ionic compound.
<h3>Explanation</h3>
Find the two elements on a periodic table:
- Potassium- K- on the left end of period four.
- Oxygen- O- near the right end of periodic two.
Elements on the bottom-left corner of the periodic table are metals. Those on the top-right corner are nonmetals.
- Potassium is a metal,
- Oxygen is a nonmetal.
A metal and a nonmetal combine to form an ionic compound. Potassium oxide is likely to be an ionic compound. It contains two types of ions:
- Potassium ions: Potassium is group 1 of the periodic table. It is an alkaline metal. Like other alkaline metals such as sodium Na, potassium K tends to lose one electron and form ions of charge +1 in compounds. The ion would be K⁺.
- Oxide ions from oxygen: Oxygen is the second most electronegative element on the periodic table. It tends to gain two electrons and form the oxide ion
when it combines with metals.
The two types of ions carry opposite charges. They shall pair up at a certain ratio such that they balance the charge on each other. The charge on each
ion is twice that on a
ion. Each
would pair up with two
. Hence the subscript in the formula:
.
There are two classes of compounds:
- Covalent compounds, which need prefixes, and
- Ionic compounds, which need no prefix.
Prefixes are needed only in covalent compounds. For instance in the covalent compound carbon dioxide
, the prefix di- indicates that there are two oxygen atoms in the formula
. However, there's no need for prefix in ionic compounds such as
.
This is because copper is a transition metals.
Transition metals don't have a definite charge, you can see this on the periodic table. However, Alkali Earth, Alkali, Metalloids, Non-metals, Halogens, Noble Gases, etc, all have a specified charge.
Although, there are exceptions: Zinc, Gold, and Cadmium.
Aluminum is a poor metal, but it has it's own charge (3+).
Therefore, Copper has roman numerals due to the fact that it's a transition metal and Aluminum is a poor metal.
Hope this helps!