Home
Class 12
CHEMISTRY
An element X having vapour density equal...

An element X having vapour density equal to 40 in gaseous state undergoes crystal formation at low temperature in FCC pattern. Number of unit cells in `1280 g` of X is represented by `nxxN_(A).` Then the value of 'n' is:

A

`1`

B

`2`

C

`3`

D

`4`

Text Solution

Verified by Experts

The correct Answer is:
D
`M.wt=80`
No. of unit cells `=(1280)/(80xx4)=4`
Promotional Banner

Topper's Solved these Questions

Similar Questions

Explore conceptually related problems

An element X (At,wt = 80 g//mol) having fcc structure, calculate the number of unit cells in 8g of X

A metallic element crystallizes in simple cubic lattice. Each edge length of the unit cell is 3 Å.The density of the element is 8g//c c . Number of unit cells in 108 g of metal is

Number of crystal systems having only 2 types of bravais lattices = x, number of crystal system having at least two interfacial angles equal = y and number of crystal systems having all the three edge lengths equal = z. Then find the value of x xx y xx z.

A crystalline solid of a pure substance has a face-centred cubic structure with a cell edge of 400 pm. If the density of the substance in the crystal is 8 g cm^(-3) , then the number of atoms present in 256g of the crystal is N xx 10^(24) . The value of N is

An element 'x' (Atomic mass = 40 g mol^(-1) ) having f.c.c. structure has unit cell edge length of 400 pm. Calculate the density of 'x' and the number of unit cells in 4 g of 'x'

An element 'X' (At. Mass = 40 g mol^(-1) ) having f.c.c structure has unit cell edge length of 400 pm . Calculate the density of 'X' and the number of unit cells in 4 g of 'X' . (N_(A) = 6.022 xx 10^(23) mol^(-1)) .

An element A (Atomic weight =100 ) having b.c.c. structure has unit cell edge length 400 pm. Calculate the density of A, number of unit cells and number of atoms in 10 g of A.

A solution which remains in equilibrium with undissolved solute , in contact , is said to be saturated . The concentration of a saturated solution at a given temperature is a called solubility . The product of concentration of ions in a saturated solution of an electrolyte at a given temperature is called solubility product (K_(sp)) . For the electrolyte A_(x),B_(y) with solubility S. The solubility product (K_(sp)) is given as K_(sp) = x^(x) xx y^(y) xx S^(x-y) . While calculating the solubility of a sparingly . soluable salt in the presence of some strong electrolyte containing a common ion , the common ion concentration is practically equal to that of strong electrolyte containing a common ion . the common ion soncentration is practically equal to that of strong electrolyte . If in a solution , the ionic product of an electroylte exceeds its K_(sp) value at a particular temperature , then precipitation occurs . If two or more electrolyte are presentt in the solution , then by the addition of some suitable reagent , precipitation generally occurs in increasing order of their k_(sp) values . Solubility of some sparingly soluable salts , is sometimes enhanced through complexation . While we are calculating the solubility of some sparingly or pH of an electrolyte , the nature of cation of anion should be checked carefully whether there ion (s) are capable of undergoing hydrolysis or not . If either or both of the ions are capable of undergoing hydrolysis , it should be taken into account in calculating the solubility . While calculating the pH of an amphiprotic species , it should be checked whether or not cation can undergo hydrolysis . Total a_(H^(-)) = sqrt(K_(a_(1)xxK_(a_(2)))) (if cation do not undergo hydrolysis ) a_(H^(+)) = sqrt(K_(a_(1))((K_(w))/(K_(b)) - K_(a_(2)))) (if cation also undergoes hydrolysis ) where symbols have usual meaning . Solubility of solids into liquids is a function of temperature alone but solubility of gases into liquids is a function of temperature as well as pressure . The effect of pressure on solubility of gases into liquids is governed by Henry's law . The solubility of PbSO_(4) in water is 0.0303 g/l at 25^(@)C , its solubility product at that temperature is

A solution which remains in equilibrium with undissolved solute , in contact , is said to be saturated . The concentration of a saturated solution at a given temperature is a called solubility . The product of concentration of ions in a saturated solution of an electrolyte at a given temperature is called solubility product (K_(sp)) . For the electrolyte A_(x),B_(y) with solubility S. The solubility product (K_(sp)) is given as K_(sp) = x^(x) xx y^(y) xx S^(x-y) . While calculating the solubility of a sparingly . soluable salt in the presence of some strong electrolyte containing a common ion , the common ion concentration is practically equal to that of strong electrolyte containing a common ion . the common ion soncentration is practically equal to that of strong electrolyte . If in a solution , the ionic product of an electroylte exceeds its K_(sp) value at a particular temperature , then precipitation occurs . If two or more electrolyte are presentt in the solution , then by the addition of some suitable reagent , precipitation generally occurs in increasing order of their k_(sp) values . Solubility of some sparingly soluable salts , is sometimes enhanced through complexation . While we are calculating the solubility of some sparingly or pH of an electrolyte , the nature of cation of anion should be checked carefully whether there ion (s) are capable of undergoing hydrolysis or not . If either or both of the ions are capable of undergoing hydrolysis , it should be taken into account in calculating the solubility . While calculating the pH of an amphiprotic species , it should be checked whether or not cation can undergo hydrolysis . Total a_(H^(-)) = sqrt(K_(a_(1)xxK_(a_(2)))) (if cation do not undergo hydrolysis ) a_(H^(+)) = sqrt(K_(a_(1))((K_(w))/(K_(b)) - K_(a_(2)))) (if cation also undergoes hydrolysis ) where symbols have usual meaning . Solubility of solids into liquids is a function of temperature alone but solubility of gases into liquids is a function of temperature as well as pressure . The effect of pressure on solubility of gases into liquids is governed by Henry's law . The solubility of BaSO_(4) in 0.1 M BaCl_(2) solution is (K_(sp) " of " BaSO_(4) = 1.5 xx 10^(-9))

ALLEN-TEST PAPERS-part-2 Chemistry
  1. If 250 mL of N(2) over water at 30^(@)C and a total pressure of 740 t...

    Text Solution

    |

  2. If the density of a mixture of O(2)&N(2) at N.T.P. is 1.258 g//l. The...

    Text Solution

    |

  3. An element X having vapour density equal to 40 in gaseous state underg...

    Text Solution

    |

  4. It was found that in 30 unit cells of ZnS, four atoms are of trivalent...

    Text Solution

    |

  5. A 45 ml mixture of hydrogen and oxygen is sparked to form liquid water...

    Text Solution

    |

  6. H(2)O(2)+2KIoverset(40% "yield")rarrI(2)+2KOH H(2)O(2)+2KMnO(4)+3H(2...

    Text Solution

    |

  7. In the reaction, I(2)+2S(2)O(3)^(2-) rarr 2I^(-)+S(4)O(6)^(2-).

    Text Solution

    |

  8. conductometric titration curve of a equimolar mixture of a HCl and HCN...

    Text Solution

    |

  9. 100 ml 0.04 M HA (K(a)=10^(-5)) and 100 mI 0.8 M HB (K(a) = 10^(-6)) ...

    Text Solution

    |

  10. In an aqueous solution of voume 1000 ml, the following reation reached...

    Text Solution

    |

  11. A buffer solution contains 0.04 M HA and 0.01 M CaA(2). If K(b) of A^(...

    Text Solution

    |

  12. Which of the following is the CORRECT of ionic radii?

    Text Solution

    |

  13. The compound which undergoes only racemisation on heating is

    Text Solution

    |

  14. Which statement is true

    Text Solution

    |

  15. The solubility product of Fe(OH)3 is 1xx10^(-36) What is the minimum c...

    Text Solution

    |

  16. Which is/are correct statements about following equilibrium? N(2)O(...

    Text Solution

    |

  17. The CORRECT order (s) regarding the atomic size is/are

    Text Solution

    |

  18. Which of the following species having same value of sigma^** (Screenin...

    Text Solution

    |

  19. Select the CORRECT statement (s):

    Text Solution

    |

  20. Choose the CORRECT statement(s) regarding the compound C(6)H(12)

    Text Solution

    |