Answer:
3p^2
Explanation:
after filling 3s^2 only two electrons left out of 14 so the next sub shell is 3p therefore ,X represents 3p^2
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").
Condensation is the change in state of matter from gas to liquid.
The atomic number of an element is based on the number of protons in the atomic nuclei of its atoms.