The correct order of the packing efficiency in different types of unit cells is-

1. Fcc < Bcc < Simple cubic

2. Fcc > Bcc > Simple cubic

3. Fcc < Bcc > Simple cubic

4. Bcc < Fcc > Simple cubic

Subtopic: Density & Packing Fraction |

86%

From NCERT

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

Links

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

The most efficient packing is present in -

1. HCP and BCC

2. HCP and CCP

3. BCC and CCP

4. BCC and Simple cubic cell

Subtopic: Density & Packing Fraction |

82%

From NCERT

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

An element has a body-centered cubic (BCC) structure with a cell edge of 288 pm. The atomic radius is:

1. $\frac{\sqrt{2}}{4}\times 288$ pm

2. $\frac{4}{\sqrt{3}}\times 288$ pm

3. $\frac{4}{\sqrt{2}}\times 288$ pm

4. $\frac{\sqrt{3}}{4}\times 288$ pm

Subtopic: Introduction & Crystal System | Density & Packing Fraction |

81%

From NCERT

NEET - 2020

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

Links

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

The formula of nickel oxide with metal deficiency defect in its crystal is $N{i}_{0.98}O$. The crystal contains ${\mathrm{Ni}}^{2+}\mathrm{and}{\mathrm{Ni}}^{3+}$ ions. The fraction of nickel existing as $N{i}^{2+}$ ions in the crystal is-

1. 0.96

2. 0.04

3. 0.50

4. 0.31

Subtopic: Density & Packing Fraction |

75%

From NCERT

NEET - 2019

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

A metal has a fcc lattice. The edge length of the unit cell is 404 pm. The density of the metal is 2.72 g cm^{–3}. The molar mass of the metal is:

(N_{A} Avogadro's constant = 6.02 × 10^{23} mol^{–1})

1. 30 g mol^{–1}

2. 27 g mol^{–1}

3. 20 g mol^{–1}

4. 40 g mol^{–1}

2. 27 g mol

3. 20 g mol

4. 40 g mol

Subtopic: Density & Packing Fraction |

74%

From NCERT

AIPMT - 2013

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

Links

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

The anions (A) form hexagonal closest packing and atoms (C) occupy only 2/3 of octahedral voids
in it. The general formula of the compound is-

1. CA

2. CA_{2}

3. C_{2}A_{3}

4. C_{3}A_{2}

Subtopic: Density & Packing Fraction |

74%

From NCERT

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

A metal crystallizes with a fcc lattice. The edge of the unit cell is 408 pm. The diameter of the metal atom is:

1. 288 pm

2. 408 pm

3. 144 pm

4. 204 pm

Subtopic: Density & Packing Fraction |

73%

From NCERT

AIPMT - 2012

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

Links

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

A solid has a bcc structure. If the distance of closest approach between the two atoms is 1.73 Å, then the edge length of the cell is:

1. 200 pm

2. $\raisebox{1ex}{$\sqrt{3}$}\!\left/ \!\raisebox{-1ex}{$\sqrt{2}$}\right.$ pm

3. 142.2 pm

4. $\sqrt{2}$pm

Subtopic: Density & Packing Fraction |

65%

From NCERT

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Copper crystallizes into an fcc lattice with an edge length of 3.61 × 10^{−8} cm. The density of copper crystal will be -

1. 7.46 g cm^{-3}

2. 9.67 g cm^{-3}

3. 8.96 g cm^{-3}

4. 5.63 g cm^{-3}

Subtopic: Density & Packing Fraction |

50%

From NCERT

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Niobium crystallizes in body-centred cubic structure. If the density is 8.55 g cm^{−3}, the atomic radius of niobium (atomic mass 93 u) is -

1. 13.32 nm

2. 12.32 nm

3. 14.32 nm

4. 15.32 nm

Subtopic: Density & Packing Fraction |

From NCERT

To view explanation, please take trial in the course.

NEET 2025 - Target Batch

Hints

Links

To view explanation, please take trial in the course.

NEET 2025 - Target Batch