Hey there! Sign in to join this conversationNew here? Join for free
    • Thread Starter
    Offline

    0
    ReputationRep:
    A sample of gallium, Ar=69.7 was anysed and was found to consist of 65% Ga-69 and one other isotope. Determine the mass number of the other isotope in the sample of gallium
    Offline

    19
    ReputationRep:
    What have you tried so far?
    Offline

    3
    ReputationRep:
    (Original post by mydearestpotato)
    A sample of gallium, Ar=69.7 was anysed and was found to consist of 65% Ga-69 and one other isotope. Determine the mass number of the other isotope in the sample of gallium
    Lets say 1% = 1 atoms

    so 100 atoms = 100%

    Therefore total mass of 100 atoms = Ar x 100.

    Therefore total mass of 100 atoms = (Y x M) + (Z x C).

    Where, Y and Z are the mass of the isotopes, and M and C are the number of atoms (uses the fact that 1 atoms = 1%).

    NOTE: Just remember Ar is the weighted mean mass of all the isotopes taking in account there abundance. So if you have 35-cl and 37-cl, the mean will not be 36? why because there might be more 35 than 37.
 
 
 
Poll
Do you agree with the PM's proposal to cut tuition fees for some courses?

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.