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Radium disintegrates at an average rate ...

Radium disintegrates at an average rate of `2.24 xx 10^13` `alpha`-particles per minute. Each a-particle takes up two electrons from the air and becomes a neutral helium atom. After 420 days, helium gas collected was 0.5 rnL, measured at 27°C and 750 mmHg. Calculate the Avogadro constant.

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The correct Answer is:
`6.7 xx 10^(23)`
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RC MUKHERJEE-ELEMENTARY PROBLEMS BASED ON DEFINITION OF MOLE: THE MOLE CONCEPT -PROBLEMS (ANSWERS BRACKETED WITH EQUATIONS)
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  5. A sample of potato starch was ground in a ball mill to give a starchli...

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  6. The dot at the end of this sentence has a mass of about one microgram....

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  7. To what volume must 50 mL of 3.50 M H2SO4 be diluted in order to make ...

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  8. Sulphur molecules exist under various conditions as S(8), S(6), S(4), ...

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  9. Two minerals that contain Cu are CuFeS(2) and Cu(2)S. What mass of Cu(...

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  10. What is the maximum number of moles of CO(2) that could be obtained fr...

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  11. What mass of NaCl would contain the same total number of ions as 245 g...

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  12. An unknown sample weighing 1.5 g was found to contain only Mn and S. T...

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  13. The two sources of Zn, that is, ZnSO(4) and Zn(CH(3)COO)(2)2.H(2)O, ca...

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  14. How many moles of H2O form when 25.0 mL of 0.10 M HNO3 solution is com...

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  15. Which would be larger: an atomic mass unit based on the current standa...

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  16. The enzyme carbonic anhydrase catalyses the hydration of CO(2). This r...

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  17. An oxybromo compound, KBrO(x) where x is unknown, is analysed and fou...

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  18. Radium disintegrates at an average rate of 2.24 xx 10^13 alpha-particl...

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  19. If the value of Avogadro number is 6.023 xx 10^23 "mol"^(-1) and the ...

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  20. Three moles of B(2)H(6) are completely reacted with methanol. The numb...

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