How many moles are represented by 9.34 x 1021 sodium atoms a. 1.25x10^2 moles

b. 1.55x10^3 moles

c. 1.55x10^2 moles

d. 1.55 moles

1.55×10⁻² moles of sodium

Explanation:

Given data:

Number of atoms of sodium = 9.34×10²¹ atoms

Number of moles of sodium = ?

Solution:

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.

1 mole = 6.022 × 10²³ atoms

9.34×10²¹ atoms × 1 mol / 6.022 × 10²³ atoms

1.55×10⁻² mol

56 moles of   lieter in chemistry

definition

                    entropy is a measure of the randomness or the extent of disorder of a chemical process.

                      enthalpy is a measure of the heat change of a reaction occurring at a constant pressure.

measurement units:

                        entropy is measured in joule per kelvin (jk⁻¹)   whereas enthalpy is measured in joule per mole (jmol⁻¹)

requirements:

                            entropy has no requirements or limits, and its change is measured by the division between the heat change of the chemical process and the temperature.

                              in contrast, enthalpy can only be related to the heat change of the reaction under standard conditions.