mass of 2 * 10^21 number of atoms of an element is 0.4g. what is the mass of 0.5 mole of the element?

The mass of 0.5 moles of the element : 60.241 g

Given

mass of 2 x 10²¹ number of atoms of an element is 0.4 g

Required

the mass of 0.5 mole

Solution

Find relative atomic mass of the element(Ar)

mol of 2 x 10²¹ atoms :

the mass of 0.5 moles :

the only liquid elements at standard temperature and pressure are bromine (br) and mercury (hg). although, elements caesium (cs), rubidium (rb), francium (fr) and gallium (ga) become liquid at or just above room temperature.

explanation: