Question
Explain the unit of mass.
✓
Answer
→The mass of an atom is very small compared to a kilogram. Kilogram is not a very convenient unit to measure such small quantities.
→'Atomic mass unit' is used to measure the mass of an atom.
• Definition :
→The twelfth part of the mass of unexcited carbon $\left( C ^{12}\right)$ atom is called $1 u$ (amu).
$1 u=1.66 \times 10^{-27} kg$
(approximate mass of proton)
→"A technique called mass spectrography is used to measure the mass of atom".
→Accurate measurements of atomic masses is carried out with a mass spectrometers.
→'Atomic mass unit' is used to measure the mass of an atom.
• Definition :
→The twelfth part of the mass of unexcited carbon $\left( C ^{12}\right)$ atom is called $1 u$ (amu).
$1 u=1.66 \times 10^{-27} kg$
(approximate mass of proton)
→"A technique called mass spectrography is used to measure the mass of atom".
→Accurate measurements of atomic masses is carried out with a mass spectrometers.
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