Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • Engineering
  • Which element has a  line of wavelength <img alt="\mathrm{ 1.785 \, \, \AA}" src="/latex-image/?%5Cmathrm%7B%201.78

Which element has a \mathrm{K}_\alpha line of wavelength \mathrm{ 1.785 \, \, \AA} ? 

Option: 1

Copper


Option: 2

Cobalt


Option: 3

Sodium


Option: 4

Aluminium


Answers (1)

best_answer

We know that, \frac{1}{\lambda_{\mathrm{k}_\alpha}}=\mathrm{R}(\mathrm{Z}-1)^2\left(\frac{1}{1^2}-\frac{1}{2^2}\right)

                 (Z-1)^2=\frac{4}{3} \times \frac{1}{\lambda_{k_\alpha} R}=680

                 \begin{aligned} & (Z-1)=26 \\ & Z=27 \rightarrow \text { cobalt } \end{aligned}

 

Posted by

Rishi

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE

Similar Questions

Trending Articles/News

anam-khan

JEE Main 2025 registration ends tomorrow; changes introduced in exam this year
anam-khan

BTech Admission 2025 Live: JEE Mains registrations closing tomorrow; VITEEE, MET exam dates out
anam-khan

JEE Main 2025 Live: NTA to close JEE registration on Friday; apply at jeemain.nta.nic.in, correction window

Latest Question