Periodic Classification of Elements — Science STD 10 — Question
CBSE BoardEnglish MediumSTD 10SciencePeriodic Classification of Elements1 Mark
MCQ
The number of elements known in Mendeleev's presented periodic table is:
A
$50$
B
$90$
✓
$63$
D
$102$
✓
Answer
Correct option: C.
$63$
In Mendeleev’s periodic table, elements were placed based on the atomic mass, and chemical properties.
During Mendeleev’s work, only $63$ elements were found.
After studying the properties of all elements, he found that the properties of elements were related to atomic mass.
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