easechemistry

Points to Recall Mole is a basic physical quantity for measuring quantity of a substance in chemistry. There is no physical balance or device to measure moles of a substance directly . Firstly we take mass( grams) by physical balance then we convert this mass into moles. Molar Mass is calculated simply by  multiplying relative masses - which are obtained from periodic table- to Molar mass constant -which is 1g/mol. Like Relative atomic of potassium (K) = 39.01 a.m.u Molar Mass of K =39.01 x 1g/mol= 39.01g/mol Conversion Factor | Definition| "Conversion factor is a ratio - this ratio is always equal to 1 - used to covert one unit into other unit. Units are inter-converted simply by multiplying or dividing the suitable conversion factor". For Mole-Mass conversions the prior information to make conversions factors is: 1 mol.= Molar Mass(g) So, the two conversion factor will be (i) mol/g  (ii) g/ mol Note: select the conversion factor in such a way that same units cut each oth...

Conversion Factors|Definition| "Conversion factor is a ratio - this ratio is always equal to 1 - used to covert one unit into other unit. Units are inter-converted simply by multiplying or dividing the suitable conversion factor". For conversion, we should have appropriate prior information.For instance,  if we want to inter-convert " inches " & " feet " we should have prior information  like,  1 foot = 12 inches  If we want to inter-convert " hours"&  " minutes"  then we should know, 1 hour= 60 minutes Few useful Conversion Factors Examples Dr. Ali measured mass of a sample , as 0.98lb later on his lab attendant needs to be take this mass in kilograms. What attendant will do to convert pounds into kilograms? Attendant knows   1 kilogram = 2.2 lb Form above prior information , attendant gets two conversion Factors.we can see those two conversion factors from above table, 1kg/ 2.2 lb   and     2.2lb/1kg Select...