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How many unit cells are present in a cube shaped ideal crystal of NaCl of mass 1g, given the atomic mass of Na and Cl? I did it like this- the structure is a fcc > 1 Na and 3Cl > Mass of 1 unit cell = mass of 1Na + mass of 3 Cl amu. Found it out then I converted it to gms. Now, P unit cells x mass of 1 unit cell = 1 gm. Found P , which is the final answer. I got the answer to be 4x 10^21, but the correct answer is 2.57 x 10^21. where did I go wrong?
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How many unit cells are present in a cube shaped ideal crystal of NaCl...
**Calculating the number of unit cells in a cube-shaped ideal crystal of NaCl**

To determine the number of unit cells in a cube-shaped ideal crystal of NaCl, we need to consider the crystal structure and the mass of the crystal.

**1. Crystal structure**
NaCl adopts a face-centered cubic (fcc) crystal structure, where each ion is surrounded by six ions of the opposite charge. In this structure, Na+ ions occupy the corners of the cube, while Cl- ions occupy the face centers.

**2. Mass of the crystal**
The mass of the crystal is given as 1g. We need to determine the mass of one unit cell in order to calculate the number of unit cells present.

**3. Mass of one unit cell**
In an fcc crystal, there is one Na+ ion at each corner and one Cl- ion at each face center. Therefore, there are a total of 8 Na+ ions and 6 Cl- ions in one unit cell.

The atomic mass of Na is approximately 23 g/mol, and the atomic mass of Cl is approximately 35.5 g/mol. Hence, the mass of one unit cell can be calculated as follows:

Mass of 1 unit cell = (8 * atomic mass of Na) + (6 * atomic mass of Cl)
= (8 * 23 g/mol) + (6 * 35.5 g/mol)
= 184 g + 213 g
= 397 g

**4. Calculating the number of unit cells**
Now, we can use the mass of one unit cell and the given mass of the crystal to calculate the number of unit cells present.

Number of unit cells = (mass of the crystal) / (mass of 1 unit cell)
= 1g / 397 g
= 0.0025

However, we need to convert this value into scientific notation.

0.0025 = 2.5 x 10^-3

Therefore, the number of unit cells in the cube-shaped ideal crystal of NaCl with a mass of 1g is approximately 2.5 x 10^(-3) or 2.5 x 10^(-3) x 10^21 = 2.5 x 10^18.

**Conclusion**
The correct answer for the number of unit cells in a cube-shaped ideal crystal of NaCl with a mass of 1g is approximately 2.5 x 10^18, not 2.57 x 10^21. It seems there was an error in your calculations or conversion.
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How many unit cells are present in a cube shaped ideal crystal of NaCl of mass 1g, given the atomic mass of Na and Cl? I did it like this- the structure is a fcc > 1 Na and 3Cl > Mass of 1 unit cell = mass of 1Na + mass of 3 Cl amu. Found it out then I converted it to gms. Now, P unit cells x mass of 1 unit cell = 1 gm. Found P , which is the final answer. I got the answer to be 4x 10^21, but the correct answer is 2.57 x 10^21. where did I go wrong?
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How many unit cells are present in a cube shaped ideal crystal of NaCl of mass 1g, given the atomic mass of Na and Cl? I did it like this- the structure is a fcc > 1 Na and 3Cl > Mass of 1 unit cell = mass of 1Na + mass of 3 Cl amu. Found it out then I converted it to gms. Now, P unit cells x mass of 1 unit cell = 1 gm. Found P , which is the final answer. I got the answer to be 4x 10^21, but the correct answer is 2.57 x 10^21. where did I go wrong? for NEET 2024 is part of NEET preparation. The Question and answers have been prepared according to the NEET exam syllabus. Information about How many unit cells are present in a cube shaped ideal crystal of NaCl of mass 1g, given the atomic mass of Na and Cl? I did it like this- the structure is a fcc > 1 Na and 3Cl > Mass of 1 unit cell = mass of 1Na + mass of 3 Cl amu. Found it out then I converted it to gms. Now, P unit cells x mass of 1 unit cell = 1 gm. Found P , which is the final answer. I got the answer to be 4x 10^21, but the correct answer is 2.57 x 10^21. where did I go wrong? covers all topics & solutions for NEET 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for How many unit cells are present in a cube shaped ideal crystal of NaCl of mass 1g, given the atomic mass of Na and Cl? I did it like this- the structure is a fcc > 1 Na and 3Cl > Mass of 1 unit cell = mass of 1Na + mass of 3 Cl amu. Found it out then I converted it to gms. Now, P unit cells x mass of 1 unit cell = 1 gm. Found P , which is the final answer. I got the answer to be 4x 10^21, but the correct answer is 2.57 x 10^21. where did I go wrong?.
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