Turn on thread page Beta
    • Thread Starter
    Offline

    0
    ReputationRep:
    I don't understand how to calculate the answer to this question: The half-life of one radioactive isotope is 71 days. By starting with 16g, calculate the mass of the remains that are left of this isotope after 213 days.
    Offline

    3
    ReputationRep:
    (Original post by Tayla1998)
    I don't understand how to calculate the answer to this question: The half-life of one radioactive isotope is 71 days. By starting with 16g, calculate the mass of the remains that are left of this isotope after 213 days.
    doesn't this mean every 71 days 1 half-life is completed i.e. the mass of the radioactive isotope is halved?
    • Community Assistant
    • Study Helper
    Offline

    17
    ReputationRep:
    Community Assistant
    Study Helper
    (Original post by Tayla1998)
    I don't understand how to calculate the answer to this question: The half-life of one radioactive isotope is 71 days. By starting with 16g, calculate the mass of the remains that are left of this isotope after 213 days.
    Three half lives have passed after 213 days (213/71 = 3)

    After one half life 8g remains
    After two half lives 4g remains
    After three half lives 2g remains
    • Thread Starter
    Offline

    0
    ReputationRep:
    (Original post by charco)
    Three half lives have passed after 213 days (213/71 = 3)

    After one half life 8g remains
    After two half lives 4g remains
    After three half lives 2g remains
    Thanks for your help.
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: March 10, 2016
The home of Results and Clearing

2,688

people online now

1,567,000

students helped last year

University open days

  1. SAE Institute
    Animation, Audio, Film, Games, Music, Business, Web Further education
    Thu, 16 Aug '18
  2. Bournemouth University
    Clearing Open Day Undergraduate
    Fri, 17 Aug '18
  3. University of Bolton
    Undergraduate Open Day Undergraduate
    Fri, 17 Aug '18
Poll
Do you want your parents to be with you when you collect your A-level results?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.