In case of a copper atom, Mass Number is 64 and atomic number is 29. What will be the number of neutrons in a copper atom?
35
Finding Neutrons in a Copper Atom
The composition of an atom is determined by the number of protons, neutrons, and electrons it contains. For a neutral atom, the number of protons is equal to the number of electrons. The identity of an element is defined by the number of protons, which is also known as the atomic number.
Understanding Atomic Number and Mass Number
- Atomic Number (Z): This is the number of protons in the nucleus of an atom. It uniquely identifies an element. In a neutral atom, Atomic Number (Z) is also equal to the number of electrons.
- Mass Number (A): This is the total number of protons and neutrons in the nucleus of an atom. Electrons contribute very little to the mass, so they are not included in the mass number.
The relationship between mass number, atomic number, and the number of neutrons is given by the formula:
\( \text{Mass Number (A)} = \text{Number of Protons (Z)} + \text{Number of Neutrons (n)} \)
From this formula, we can find the number of neutrons:
\( \text{Number of Neutrons (n)} = \text{Mass Number (A)} - \text{Atomic Number (Z)} \)
Calculating Neutrons for a Copper Atom
We are given the following information for a copper atom:
- Mass Number (A) = 64
- Atomic Number (Z) = 29
Using the formula for the number of neutrons:
\( n = A - Z \)
Substitute the given values:
\( n = 64 - 29 \)
Performing the subtraction:
\( n = 35 \)
Therefore, the number of neutrons in this copper atom is 35.
Let's look at the options provided:
| Option | Value |
|---|---|
| 1 | 35 |
| 2 | 64 |
| 3 | 93 |
| 4 | 29 |
The calculated number of neutrons is 35, which corresponds to option 1.
Important Questions from Atoms
The ratio of radii of two nuclei having atomic mass numbers 27 and 8 respectively, will be:
The ratio of the volume of an atom to the volume of the nucleus is (in terms of order of magnitude):
If $M$ is the mass of water that rises in a capillary tube of radius $r$, then what would be the total mass of water that rises if a capillary tube of radius $r$ and another capillary tube of radius $2r$ are simultaneously placed in water, assuming identical liquid and material properties?
A $Be^{3+}$ ion, initially in its second excited state, absorbs a photon of wavelength $601.6\text{ A}$. The radius of the ion in the resulting excited state in terms of Bohr radius $a_0$ will be (Take $hc = 12500\text{ eV-A}$)
Which of the following statement is CORRECT with reference to the process of Ionization?
