The density of solid fe is 7.87 g/cm3. how many atoms are present per cubic centimeter of fe?

The number of iron atoms in given amount is

Explanation:

Density of a substance is defined as the ratio of its mass and volume. The chemical equation representing density of a substance is:  

We are given:

Density of iron =

Volume of iron =

Putting values in above equation, we get:

To calculate the number of moles, we use the equation:

Given mass of iron = 7.87 g

Molar mass of iron = 55.65 g/mol

Putting values in above equation, we get:

According to mole concept:

1 mole of an element contains number of atoms.

So, 0.141 moles of iron will contain = number of atoms.

Hence, the number of iron atoms in given amount is

6.4 cm (max) - 25 cm (min)

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.