How to calculate atomic mass of an element, Chemistry

Assignment Help:

Q. How to calculate atomic mass of an element?

Copper survive as a mixture of two isotopes. The lighter isotope (Cu-63) amid 29 protons and 34 neutrons makes up 69.17% of copper atoms. The heavier isotope (Cu-65) with 29 protons and 36 neutrons constitutes the remaining 30.83% of copper atoms. The atomic mass of Cu-63 is 62.930 amu, as well as the atomic mass of Cu-65 is 64.928 amu. Use the data above to calculate the atomic mass of copper.

For a trouble that has several numerical values it is wise to organize the data into a table.

 

Isotope

Copper-63

Copper-65

Number of protons

29

29

Number of neutrons

34

36

Atomic  mass

62.930 amu

64.928 amu

Abundance

69.17%

30.83%

First compute the contribution of each isotope to the average atomic mass being sure to convert each percent to a fractional abundance.

Mass contribution = mass of isotope *   abundance of isotope

For Cu-63

Mass contribution = 62.930 amu * 0.6917 = 43.53 amu

For Cu-65

Mass contribution = 64.928 amu * 0.3083 = 20.02 amu

The average atomic mass of the element is the total of the mass contributions of each isotope.

Atomic mass Cu = mass contribution Cu-63+ mass contribution Cu-65

Atomic mass Cu = 43.529 amu + 20.017 amu = 63.546 amu


Related Discussions:- How to calculate atomic mass of an element

Colloids, what are the chemical properties of colloids

what are the chemical properties of colloids

Titration, what is the method to doing potentiometric titration

what is the method to doing potentiometric titration

Thermodynamics, Calculate the free energy change of following reaction at29...

Calculate the free energy change of following reaction at298 kelvin H2+I2=2HI if the enthalpy change is 51.8816kj and the entropy change is 166.15j is this reaction thermodyanamica

Important synthetic rubbers: neoprene, Neoprene (GR: or Polychloroprene or ...

Neoprene (GR: or Polychloroprene or Dupe) Preparation: Neoprene is prepared by the free radical polymerisation of chloroprene in an emulsion system. Starting materials are ac

Project, to study the presence of aroma,taste, ph value and tannic acid of ...

to study the presence of aroma,taste, ph value and tannic acid of different tea leaves

Symmetry operations and symmetry elements, Symmetry is a property of molecu...

Symmetry is a property of molecules having more than one atom of the same kind, with equal bond lengths and/or bond angles. As like the high symmetry of the SF6 molecule (Fig. 1. a

Series limit for balmer series of h-spectra, The series limit for Balmer se...

The series limit for Balmer series of H-spectra is: (1) 3800          (2) 4200         (3) 3646                (4) 4000 Ans:  3646

Explain the hydrogenation, Which of the following rate equations is correct...

Which of the following rate equations is correct, if the hydrogenation of  the adsorbed intermediate is the slowest step of the reaction?   When zinc oxide is used as

Aluminium used as a reducing agent of metals. why?, The free energy change...

The free energy change for the formation of oxide of aluminium is highly negative ( -1000 to -1100) so , it can easily reduce any metal oxide abve it easily in ellingham diamgram a

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd