Question

Atomic mass unit???????????????

Answer 1

moles H3PO4 = 87.0 g / 97.9937 g/mol = 0.8878 mol 
kg of water = 0.0130 kg

molality = 0.8878 mol / 0.0130 kg = 68.3 molal

Answer 2

Answer:

• this is a comparison between carbon and other gases
• in 1961 IUPAC(international union of pure applied chemistry ) selected C12 as standard unit.
• carbon 12 = C12
• 1 atomic mass unit = 1/2 mass of an atom of C12
• mass of an atom C12 = 1.99 x 10^-23g
• 1 atomic mass unit = 1/2 of 1.99 x 10^-23g
• 1amu = 1.66 x 10^-24g
• atomic mass is a number which indicates how much times the gas is heavier than 1 atomic mass unit.