How many grams are in 2.57x10^15 molecules of Co

Mass = 25.37 * 10⁻⁸ g

Explanation:

Given dа ta:

Number of grams of Co = ?

Number of molecules = 2.57*10¹⁵

Solution:

The given problem will solve by using Avogadro number.

It is the number of atoms, ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 * 10²³ is called Avogadro number.

For example,

18 g of water = 1 mole = 6.022 * 10²³ molecules of water

For Co:

2.57*10¹⁵ molecules * 1 mole / 6.022 * 10²³ molecules

0.43 * 10⁻⁸ moles

Mass of Co:

Mass = number of moles * molar mass

Mass = 0.43 * 10⁻⁸ mol * 59 g/mol

Mass = 25.37 * 10⁻⁸ g