Question
Question: Calculate the molar mass of the following compounds? A. Baking powder B. Phosphorus molecule...
Calculate the molar mass of the following compounds?
A. Baking powder
B. Phosphorus molecule
Solution
Molar mass is the mass of one mole of any substance expressed in grams. One mole is the amount of substance that contains as many particles as that are present exactly in 12gof carbon isotope 12C . One mole of any substance contains Avogadro’s number of particles or entities.
Complete step by step answer:
Let us first find out the molar mass of baking powder;
The molecular formula for baking powder is NaHCO3 . Sodium hydrogen carbonate is the chemical name for this compound
The molar mass of baking powder can be calculated from the atomic masses of sodium, hydrogen, carbon and oxygen. The molar mass is expressed in gmol−1 .So the calculation can be done as follows-
Molarmass=23+1+12+(3×16)=84gmol−1
Since the atomic masses of sodium, hydrogen, carbon and oxygen are 23,1,12,16u respectively . Nowadays amu is replaced by u . It denotes unified mass.
Phosphorus molecule:
The formula of phosphorus molecules is P4 . The atomic mass of phosphorus is 31u . So the molar mass can of phosphorus molecule can be calculated as-
Molarmass=4×31=124gmol−1 .
So the molar mass of baking powder and phosphorus molecules are 84and124gmol−1 .
Additional information:
amu is an atomic mass unit. One atomic mass unit is known as a mass exactly equal to one-twelfth of the mass of one carbon −12 atom.
Molar mass is always expressed in gmol−1 .
The baking powder is a mixture of carbonate or bicarbonate and a weak acid, it is also a dry chemical leavening agent.
Note: Phosphorus molecule has tetrahedral structure. Phosphorus can exist in several allotropes. Some of them are red phosphorous, white phosphorous, black phosphorus. Allotropes are the different structural forms of an element having different physical and chemical properties.