Answer:
The Cotton Gin
Explanation:
The cotton gin: A game-changing social and economic invention. On this day in 1793, young inventor Eli Whitney had his U.S. patent for the cotton gin approved, an invention that would definitely have an impact on social and economic conditions that led to the Civil War.
Avogadro's number represents the number of units in one mole of any substance. This has the value of 6.022 x 10^23 units / mole. This number can be used to convert the number of atoms or molecules into number of moles. We do as follows:
10 mol NH3 ( 6.022 x 10^23 molecules / 1 mol ) = 6.022x10^24 molecules NH3
When you work with molar mass, you solve for the quantity of ''Moles'' within the substance by converting Mass. The way you can tell the equation is balanced would be by knowing whether the moles were equivalent on both sides or not. Therefore, if they are equal, it is balanced considering you have the same amount of moles on each side of the equation.
The answer is B as isotopes are different versions of the same chemical element containing the same amount of protons and electrons but different amounts of neutrons.