Actually Welcome to the Concept of the Astrophysics.
Let's categorize them eventually ==>
1.) Earth ==> 1.) travels around the Sun
2.) takes 365.25 days .
2.) Moon ===> 1.) travels around the Earth
2.) Takes 27.3 days.
Answer:
A chemical change because a temperature change occurred, the solid disappeared and a gas was produces
Explanation:
Magnesium reacts with hydrochloric acid releasing energy, and leading to the formation of magnesium chloride and hydrogen gas. This is represented by the equation below:
Mg₍s₎ + 2HCl₍aq)⇒ MgCl₂₍aq₎ + H₂₍g₎
Answer:
A
Explanation:
Argon has 17 protons and 18 neutron
atomic number is the same as the protons number.
Ca₁₀(PO₄)₆(OH)₂ - hydroxyapatite
b. phosphorus (P) and calcium (Ca)
Answer:
Excited state of an electron is the state attained by an electron after it has absorbed energy and it moves further from the nucleus.
an electron is at higher energy when excited and at lower energy when at ground state.
an excited electron is less stable due to the decrease in the nuclear force of attraction and the grounded electron is more stable due to it's close distance to the nucleus.
