Home
Class 12
CHEMISTRY
19.7 kg of gold was recovered from a smu...

19.7 kg of gold was recovered from a smuggler. How many atoms of gold were recovered ? (Au = 197).

A

100

B

`6.02 xx 10^23`

C

`6.02 xx 10^24`

D

`6.02 xx 10^25`

Text Solution

Verified by Experts

The correct Answer is:
D
197 g of gold ` = 6.02 xx 10^23 ` atoms ` 19.7 xx 10^3 g` of gold
` (6.02 xx 10^23)/(197) xx 19.7 xx 10^3 = 6.02 xx 10^25`
Promotional Banner

Topper's Solved these Questions

  • SOME BASIC CONCEPTS OF CHEMISTRY

    MODERN PUBLICATION|Exercise MULTIPLE CHOICE QUESTION (LEVEL-III)|5 Videos

  • SOME BASIC CONCEPTS OF CHEMISTRY

    MODERN PUBLICATION|Exercise RECENT EXAMINATION QUESTION|15 Videos

  • SOME BASIC CONCEPTS OF CHEMISTRY

    MODERN PUBLICATION|Exercise RECENT EXAMINATION QUESTION|15 Videos

  • SOLUTIONS

    MODERN PUBLICATION|Exercise Recent Examination Questions|13 Videos

  • STATES OF MATTER

    MODERN PUBLICATION|Exercise RECENT EXAMINATION QUESTIONS|12 Videos

Similar Questions

Explore conceptually related problems

A committee of 7 has to be formed from 9 boys and 4 girls. In how many ways can this be done when the committee consists of (i) exactly 3 girls (ii) atleast 3 girls? (iii) atmost 3 girls?

Extraction of gold and silver involves leaching the metal with CN^- ion. The metal is recovered by .............

Metallic gold crystallizes in the fcc lattice. The length of the cubic unit cell is a = 4.242 A . a. What is the closest distance between gold atoms? b. How many "nearest neighbours" does each gold atom have at the distance calculated in (a) ? (c) What is the density of gold? (Aw of Au = 197.0 g mol^(-1) ) d. Prove that the packing factor for gold is 0.74 .

There are 4 students for physics, 6 students for chemistry and 7 students of mathematics gold medal. In how many ways one of these gold medals be awarded?

When cells of skeletal vacuoles of a frog were placed in a series of NaCl solutions of different concentration solution at 25^(@)C , it was observed microscopically that they remained unchaged in 0.7% solution, shrank in a more concentrated and swelled in more dilute solution. Water freezes from the 0.7% salt solutions at -406^(@)C . What is the osmotic pressure of the cell cytoplasm at 25^(@)C . (K=_(f)=1.86 kg "mol"^(-1) K)

A bolt of mass 0.3 kg falls from the ceiling of an elevator moving down with an uniform speed of 7 ms^(-1) . It hits the floor of the elevator (length of the elevator = 3m) and does not rebound. What is the heat produced by the impact? Would your answer be different if the elevator were stationary?

Metallic iron crystallizes in a particular type of cubic unit cell. The unit cell edge length is 287 pm. The density of iron is 7.87 gcm^(-3) . How many iron atoms as there within one unit cell? [Given : N_A=6.0233 xx 10^(23) , M=55.845 g mol^(-1) ]

MODERN PUBLICATION-SOME BASIC CONCEPTS OF CHEMISTRY -MULTIPLE CHOICE QUESTION (LEVEL-II)
  1. The volume of one molecule of water is (density of water = 1 g ml^(-1)...

    Text Solution

    |

  2. One mole of hydrogen peroxide (H2O2) has a mass same as that of

    Text Solution

    |

  3. 19.7 kg of gold was recovered from a smuggler. How many atoms of gold ...

    Text Solution

    |

  4. A gaseous mixture contains oxygen and nitrogen in the ratio of 1:4 by ...

    Text Solution

    |

  5. 0.5 mol of BaCl2 is mixed with 0.2 mol of Na3PO4 . The maximum numb...

    Text Solution

    |

  6. 4.0 grams of caustic soda contain

    Text Solution

    |

  7. One litre of a gas at S.T.P. weighs 1.16 g. It can possibly be

    Text Solution

    |

  8. 12 g of magnesium (atomic mass 24) on reacting completely with acid gi...

    Text Solution

    |

  9. If 224 ml of a triatomic gas has a mass of 1 g at N.T.P., then the mas...

    Text Solution

    |

  10. In the final answer of the expression ((29.2 -20.2)(1.79 xx 10^5))/(1....

    Text Solution

    |

  11. If 20.0 g of CaCO3 is treated with 200 g of HCI, how many grams of CO...

    Text Solution

    |

  12. The thickness of Milky way Galaxy is 40 Em. It can be expressed in met...

    Text Solution

    |

  13. The mass of an Al block (in grams) whose dimensions are 2.0 inch x 3....

    Text Solution

    |

  14. The volume of SO2 produced at S.T.P. by the combustion of 50 g of sul...

    Text Solution

    |

  15. What is the number of potassium atoms required to prepare 1 equivalent...

    Text Solution

    |

  16. The total number of valence electrons in 4.2 g of N(3)^(-) ions is ...

    Text Solution

    |

  17. If 22.4 ml of a triatomic gas has a mass of 0.048 g at 273K and 1 atm...

    Text Solution

    |

  18. Two elements A (at. mass 16) and B (at. mass 14) combine to form compo...

    Text Solution

    |

  19. One litre of an unknown gas weighs 1.25 g at NTP. The possible formula...

    Text Solution

    |

  20. A metal M forms an alum which contains the element potassium and is is...

    Text Solution

    |