Atomic Mass class 9

According to whom each element had a characteristic atomic mass

• Proust

• Lavoisier

• Dalton

• Newton

What is IUPAC

• International Union of Professional And Creative scientists

• International Union of Pure and Associated Chemistry

• International Union of Pure and Applied Chemists

• None of these

Which element's atom was taken by scientists in the past to measure atomic mass

• Nitrogen

• Hydrogen

• Oxygen

• Chlorine

In which year carbon-12 isotope was chosen as the standard reference for measuring atomic masses

• 1978

• 1982

• 1961

• 1954

How were relative atomic masses determined

• Law of constant proportions and compounds formed

• Law of conservation of mass and compounds formed

• Laws of chemical combinations and compounds formed

• Dalton's atomic theory

What is u

• Uniform mass

• Used mass

• Unified mass

• Unused mass

Old atomic mass unit

• u

• amu

• IUPAC

• fmu

Why was old atomic mass unit of the oxygen element considered relevant

• It reacted with a large number of elements and formed compounds

• It gave masses of most of the elements in rational numbers

• It gave masses of most of the elements in whole numbers

• Because it was artificially made

Which element was chosen as the standard reference for measuring atomic masses

• Carbon

• Oxygen

• Carbon-12 isotope

• None of these

Atomic Mass of calcium

• 38

• 27

• 32

• 40