Page 1 - 4. Home Assignment Ch-5 MENDELEEVES CLASSIFICATION

SAI International School
Class-X

Subject_ Chemistry
Ch- Periodic Classification
Sub topic- Mendeleev's Periodic Classification

Home Assignment

Objective-
Q.1 According to Mendeleef periodic law, the properties of elements are a periodic
function of their-
(a) atomic masses (b) atomic numbers
(c) atomic volumes (d) densities

Q.2 Noble gases were included in Mendelev’s periodic table in the-

(a) 1 st group (b) 7th group
(c) 8th group (d) none of these

Q.3 Mendeleev classified elements in-
(a) increasing order of atomic groups
(b) eight periods and eight groups
(c) seven periods and nine groups
(d) eight periods and seven groups

➢ For Assertion & Reason question follow the following directions.
DIRECTION: Each of these questions contains an Assertion followed by Reason.
Read them carefully and answer the question on the basis of following options. You
have to select the one that best describes the two statements.

(a) If both Assertion and Reason are correct and Reason is the correct explanation of
Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct
explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.

(d) If Assertion is incorrect but Reason is correct.
(e) If Assertion & Reason both are incorrect.

Q.4
Assertion : According to Mendeleev, properties of elements is a periodic
function of their atomic number.
Reason : Atomic number is equal to the number of protons.

Q.5
Assertion : Mendeleev arranged elements in horizontal rows and vertical
columns.

Reason : Mendeleev ignored the order of atomic weight thinking that the
atomic measurements might be incorrect.

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