Science, asked by tasneemprzd10, 1 year ago

3. An element “X” has mass number 35 and the number of neutrons, is 18. Identify

the group number and period of “X”.

Answers

Answered by aditi393

given mass no. = 35
no. of neutrons = 18
therefore no. of protons = atomic no. = 35-18 = 17
so the element X has atomic no. 17
so its group no. is 17 and period is 3

tasneemprzd10: how do we get to know the period

ampamaria2010p5kn54: IT is the number of shells

tasneemprzd10: so how do we get to know tat it has 3 shells

ampamaria2010p5kn54: by the electronic configuration

tasneemprzd10: plzz explain it I m very poor at tat

ampamaria2010p5kn54: no worries. see, they have given that mass number is 35 and number of neutrons is 18. we know that mass number= sum of neutrons + protons. so we find proton by subtracting 35-18 =17 . so 17 is the atomic number of element X. now we need to find its electronic configuration . for that we distribute the electrons into K,L,M shells. hence we get the electric configuration as 2,8,7

tasneemprzd10: k tq but how does it show tat it belongs to the third period

ampamaria2010p5kn54: because it has three shells. that determines that it belongs to period 3

tasneemprzd10: k k I get I now

Answered by ampamaria2010p5kn54

Number of protons= 35-18=17
The atom is chlorine
Electronic configuration- 2,8,7
group number- 17
period-3

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3. An element “X” has mass number 35 and the number of neutrons, is 18. Identify the group number and period of “X”.

Answers

3. An element “X” has mass number 35 and the number of neutrons, is 18. Identify

the group number and period of “X”.