CASE BASED MCQ Q no 31 35 Read the following passage and

Last updated: 6/28/2023

CASE BASED MCQ Q no 31 35 Read the following passage and answer the following questions Modern periodic table arranges the elements in the increasing order of atomic number It has 18 groups and 7 periods Atomic numbers are consecutive in a period and increases in the group in a pattern Elements are divided into four blocks s block p block d block and f block based on their electronic configuration 78 of elements are metals about 20 elements are non metals and few elements like B Si Ge As are metalloids Metallic character increases down the group but decreases along the period from left to right The physical and chemical properties vary periodic trends are observed in atomic size ionization valences Oxides of metals are basic some are amphoteric Non metals from acidic oxides some from netural oxides s block elements are soft highly reactive do note show variable oxidation states P block elements are metals non metals as well as metalloids show variable oxidation states exist as solids liquids and gases D block elements are metals from coloured ions show variable oxidation state have high melting and boiling points Lanthanoids and actinoids are f block elements form coloured ions All actinoids are radioactive 31 Assertion Modern periodic table contains 18 group 7 period Reason Atomic number are consecutive in a period and increases in the group 32 Assertion The highest oxidation state of Os is 5 Reason Osmium is a 5d block elements 33 Assertion Sixth and seventh periods in the periodic table contains 14 elements Reason In the periodic table 14 elements each of sixth from Z 58 to Z 71 and seventh periods from Z 90 to Z 103 respectively are known as lanthanoids and actinoids 34 Assertion Helium is placed in group 18 along with p block elements Reason Helium is much less reactive like other inert gases 35 Assertion Chemistry of actinoids is more complicated than lanthanoids Reason Actinoid elements are radioactive