The atomic number gives you the number of protons element x has. Since the mass of protons and neutrons are almost similar(around 1 amu), the mass number can be thought of as the sum of protons and neutrons. so if element x whose atomic number is 40 has a mass number of 82, then we know that 42 of those must be neutrons.
Answer:
Limestone is a sedimentary rock
Explanation:
1. Limestone is a carbonate sedimentary rock made up of calcite(CaCO₃).This rock type forms calcareous shells and tests of organisms that was deposited in a sedimentary basin.
Limestone is used in building and construction works. It also finds application in chemical industries.
2. Over a long period of time, we would take a look at the rock "limestone" through the rock cycle.
Limestone being a sedimentary rock would be converted to marble, a metamorphic rock if subjected to metamorphic conditions over an extensive period of time. With series of metamorphic transformation, marble can grade to higher metamorphic facies of rocks as it combines with other minerals in the crust. The minerals would eventually change and as the changed rock approaches its melting temperature, melt would result.
From the other spectrum, limestone can be weathered if subjected extensively to denudation forces such as wind, water and glaciation. Water is more potent for the chemical weathering of limestone. Limestone would easily and readily dissolve in it over a long period of time.
Stars form from an accumulation of gas and dust, which collapses due to gravity and starts to form stars. The process of star formation takes around a million years from the time the initial gas cloud starts to collapse until the star is created and shines like the sun