Placing elements into columns, groups, rows and periods that share certain properties. properties such as gas, solid and liquid determine an element physical state at room temperature.
Answer:
The energies corresponding to each of the allowed orbitals are called energy levels.
Explanation:
A scientist known as Niels Bohr put forward that electrons in an atom covers some permitted orbitals with a specific energy. In other words, the energy of an electron in an atom is not continuous, but 'quantized.' The energies corresponding to each of the allowed orbitals are called energy levels.

Answer:
The answer is 30 degrees.
Explanation:
The angle between the index and pinky fingers is 15 degrees.
Twice this angle is 2×15=30degrees.
The ions are able to carry electric current through a solution. Some liquids such as oil or alcohol do not form ions and do not conduct electricity. Vinegar is mostly water with a small amount of acetic acid in it. The acetic acid separates into ions on so that the solution conducts electricity. BRAINLIST ME PEASE
Answer: The Islamic believers traveled to Mecca once during their lives because they would perform Hajj ( this is piligrimage) and it is the main part of the islam
Explanation:
Hajj is very important to islam people so in order to do this they had to go to Mecca. Hajj is rituals and rites that need to be fulfilled. Its not the only pillar for islam but it is one out of five.