When a hydrogen atom is ionized, it splits into two components. a. Identify the two components. b. If both components have the same kinetic energy, which moves faster?

Short Answer

Expert verified
The two components are a proton and an electron. The electron moves faster.

Step by step solution

01

Identify the Components

When a hydrogen atom is ionized, it separates into two parts: a proton (positive charge) and an electron (negative charge). Therefore, the components are a proton and an electron.
02

Conservation of Energy

Since both the proton and the electron have the same kinetic energy, we need to use the relationship between kinetic energy, mass, and velocity. Kinetic energy (KE) is given by the formula: \( KE = \frac{1}{2}mv^2 \).
03

Equal Kinetic Energy

Given that the kinetic energy of both particles is the same, we equate the expressions for kinetic energy: \( \frac{1}{2}m_pv_p^2 = \frac{1}{2}m_ev_e^2 \), where \(m_p\) and \(m_e\) are the masses of the proton and electron respectively, and \(v_p\) and \(v_e\) are their respective velocities.
04

Simplifying the Equation

Cancelling out the constant \( \frac{1}{2} \) on both sides and rearranging for velocity, we get: \( m_p v_p^2 = m_e v_e^2 \). Since we need to find which particle moves faster, solve for the velocities: \( v_e^2 / v_p^2 = m_p / m_e \). Taking the square root of both sides, we find: \( v_e / v_p = \sqrt{m_p / m_e} \).
05

Comparing Masses

The mass of a proton \(m_p\) is about 1836 times the mass of an electron \(m_e\), so \( \sqrt{m_p / m_e} = \sqrt{1836} \approx 43 \). This means \( v_e / v_p \approx 43 \), so the electron moves faster.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

hydrogen atom ionization
When a hydrogen atom is ionized, it splits into two distinct charged components: a proton and an electron. This process occurs when sufficient energy is provided to overcome the binding energy that holds the electron and proton together. The result is the complete separation of the atom into these two particles.
The proton remains positively charged, while the electron carries a negative charge.
Ionization is common in various scientific fields, including plasma physics and astrophysics.
The separated proton and electron can then move independently, often requiring further analysis to understand their kinetic properties.
proton and electron masses
An important aspect of ionization is the mass difference between the proton and electron. The mass of a proton (\(m_p\)) is approximately 1836 times larger than the mass of an electron (\(m_e\)).
This significant mass difference plays a crucial role in their dynamics post-ionization.
  • Proton mass (\(m_p\)) ≈ 1.67 × 10^-27 kg.
  • Electron mass (\(m_e\)) ≈ 9.11 × 10^-31 kg.
Understanding these masses is essential when analyzing their behavior, especially in relation to their velocities and kinetic energies.
velocity and kinetic energy relationship
Kinetic energy (\(KE\)) is fundamentally dependent on both mass and velocity of a particle. It is given by the formula:

\(KE = \frac{1}{2}mv^2\)


In this equation:
  • \(m\) stands for the mass of the particle.
  • \(v\) represents the velocity of the particle.
If two particles have the same kinetic energy but different masses, the particle with the smaller mass must have a higher velocity.
This relationship can be further appreciated by rearranging the equation to solve for velocity:

\(v = \bigg( \frac{2KE}{m} \bigg)^{1/2}\)

conservation of energy in particle physics
In particle physics, the principle of conservation of energy asserts that the total energy of an isolated system remains constant over time. When a hydrogen atom ionizes, the energy used to separate the proton and electron comes primarily from the kinetic energy imparted to these particles.
This means:
  • The sum of the kinetic energy of the proton and the electron post-ionization must equal the energy initially used to ionize the atom.
For the hydrogen atom specifically, if both the proton and electron have equal kinetic energies, we can use the relationship:

\(\frac{1}{2}m_pv_p^2 = \frac{1}{2}m_ev_e^2\)


This demonstrates that their velocities can be directly compared based on their differing masses.
comparison of proton and electron velocities
Given the mass difference between a proton and an electron, the relationship between their velocities can be compared by equating their kinetic energies:

\(m_pv_p^2 = m_ev_e^2\)

Solving for the velocity ratio, we get:

\(v_e / v_p = \bigg( m_p / m_e \bigg)^{1/2}\)

Since \(m_p\) is 1836 times \(m_e\), the ratio becomes:

\(v_e / v_p = \bigg( \frac{m_p}{m_e} \bigg)^{1/2} \bigg( = \bigg( 1836 \bigg)^{1/2} \bigg( \bigg( ≈ 43\).
This implies that for the same kinetic energy, an electron moves approximately 43 times faster than a proton.
This significant difference in velocity is crucial for understanding interactions and dynamics in ionized systems.

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Most popular questions from this chapter

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