Problem 78 - General Chemistry: Principles and Modern Applications

Question

Which of the following types of radiation is deflected in a magnetic field? (a) \(X\) ray; (b) \(\gamma\) ray; (c) \(\beta\) ray; (d) neutrons.

Step-by-Step Solution

Answer

Only \(\beta\) rays from the given options are deflected in a magnetic field, as they are the only type of radiation in this list that carry a charge.

Step 1: Understand the types of radiation

It's important to first understand the properties of the given types of radiation.\n(a) \(X\) rays: These are electromagnetic radiation, not particles, and carry no charge.\n(b) \(\gamma\) rays: These are also electromagnetic radiation and carry no charge. \n(c) \(\beta\) rays: These are actually high-speed electrons (or positrons). Electrons carry a negative charge and positrons carry a positive charge. \n(d) Neutrons: These are subatomic particles that carry no charge.

Step 2: Identify which types of radiation can be deflected in a magnetic field

Since deflection in a magnetic field occurs for charged particles but not for neutral ones, you can identify which radiation types may be deflected.\n(a) \(X\) rays: As these aren't charged, they won't be deflected. \n(b) \(\gamma\) rays: As these aren't charged, they won't be deflected. \n(c) \(\beta\) rays: As these are charged, they can be deflected. \n(d) Neutrons: As these aren't charged, they won't be deflected.

Key Concepts

Magnetic Field Deflection

Understanding how magnetic fields interact with various forms of radiation is crucial in fields such as physics and engineering. A key concept to grasp is magnetic field deflection, which is the phenomenon that occurs when charged particles move through a magnetic field and experience a force perpendicular to both their direction of motion and the magnetic field lines. This results in the particle's path curving, or being 'deflected', rather than continuing in a straight line.

The degree of deflection depends on several factors such as the velocity of the particle, its charge, the strength of the magnetic field, and the angle at which the particle enters the field. Uncharged particles, like neutrons, will not experience this force and therefore travel unaffected through a magnetic field. This fundamental understanding allows scientists and engineers to influence or measure certain particle properties by using magnetic fields.

Beta Rays

Beta rays, are a form of radioactive decay and consist of high-speed electrons (beta-minus decay) or positrons (beta-plus decay). Both electrons and positrons are subatomic particles with charge, which is a pivotal property when considering their behavior in a magnetic field. Electrons have a negative charge, while positrons carry a positive charge.

Their charge is the reason why beta rays are deflected when passing through a magnetic field. This property has practical applications in many areas of research and technology, such as in radiation therapy for cancer treatment, where the path of beta rays can be precisely directed to target and destroy tumors.

Electromagnetic Radiation

Electromagnetic radiation is a fundamental phenomenon in which energy travels through space in the form of waves. This wide spectrum includes various types of radiation such as radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.

Unlike subatomic particles, electromagnetic radiation does not have mass or charge; consequently, it is not deflected by magnetic fields. X-rays and gamma rays, mentioned in the problem, belong to the high-energy end of the electromagnetic spectrum. They are used in a range of applications, from medical imaging to the treatment of cancer, and their unaffected path through magnetic fields is one reason why they are reliable for such precise purposes.

Subatomic Particles

The world at a very small scale is made up of subatomic particles, including protons, neutrons, and electrons. These are the building blocks of atoms, the smallest units of chemical elements. Protons are positively charged, neutrons are neutral, and electrons are negatively charged.

The charge of these particles is an essential property that determines how they interact with magnetic fields. Charged particles such as electrons and protons will be deflected when they move through a magnetic field, whereas uncharged particles such as neutrons will not. This fundamental principle is instrumental for technologies like particle accelerators and spectrometers, which are used for a variety of scientific explorations and practical applications.