/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 18 $$ \begin{aligned} &\tex... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 21: Problem 18

$$ \begin{aligned} &\text { Fill in the missing entries in the table below. }\\\ &\begin{array}{l} \end{array}\\\ &\begin{array}{ccccc} & & & \text { Number } & \text { Number } \\ \text { Symbol } & Z & A & \text { of Protons } & \text { of Neutrons } \\ \hline{ }^{23} \mathrm{Na} & \- & \- & \- & \- \\ \- & 45 & 103 & \- & \- \\ \- & \- & \- & 32 & 38 \\ \- & \- & 234 & 90 & - \end{array} \end{aligned} $$

Short Answer

Expert verified
Complete table with: ^{23} Na: Z=11, A=23, P=11, N=12; ^{103} Rh: P=45, N=58; ^{70} Ge: A=70; ^{234} Th: N=144.

Step by step solution

01

Understanding Atomic Number and Mass Number

The atomic number (Z) represents the number of protons in an atom and determines the element's identity. The mass number (A) is the sum of protons and neutrons in the nucleus of an atom.
02

Complete First Row ( ^{23} Na)

For sodium ( ^{23} Na), its atomic number Z is 11 because Na corresponds to sodium, which has 11 protons. The mass number A is given as 23. The number of neutrons is calculated by subtracting the atomic number from the mass number: Neutrons = A - Z = 23 - 11 = 12. Therefore, the row is completed as follows: Symbol ^{23} Na, Z = 11, A = 23, Protons = 11, Neutrons = 12.
03

Complete Second Row (Element with Z=45, A=103)

Given is Z = 45. The element with atomic number 45 is Rhodium (Rh). The mass number A is 103. The number of neutrons is calculated as Neutrons = A - Z = 103 - 45 = 58. The row is completed as follows: Symbol = ^{103} Rh, Z = 45, A = 103, Protons = 45, Neutrons = 58.
04

Complete Third Row (Protons=32, Neutrons=38)

The number of protons, Z, is given as 32, which corresponds to the element Germanium (Ge). The number of neutrons is 38. The mass number A is calculated by A = Protons + Neutrons = 32 + 38 = 70. The row is completed as follows: Symbol = ^{70} Ge, Z = 32, A = 70, Protons = 32, Neutrons = 38.
05

Complete Fourth Row (A=234, Protons=90)

The element with 90 protons (Z=90) is Thorium (Th). Given the mass number A = 234, the number of neutrons is Neutrons = A - Protons = 234 - 90 = 144. The row is completed as follows: Symbol = ^{234} Th, Z = 90, A = 234, Protons = 90, Neutrons = 144.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

Key Concepts

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

Atomic Number
The atomic number, often represented by the symbol \( Z \), is a key concept in understanding atomic structure. It stands for the number of protons in the nucleus of an atom.
This number is crucial because it defines the identity of the element. For instance, if an atom has 11 protons, it is always sodium (Na). No matter the number of neutrons or electrons, the atomic number remains fixed for a given element.
  • It's like a fingerprint for chemical elements.
  • Directly linked to the position of the element in the periodic table.
Remember, the atomic number is always a whole number and never changes for an element no matter the number of neutrons. This immutability is what makes the atomic number such a fundamental aspect of elemental identity.
Mass Number
The mass number, symbolized by \( A \), is another essential feature of atoms. It is defined as the sum of the number of protons and neutrons in an atom's nucleus. While protons define the element's identity, the mass number gives us insight into its isotopic form.
  • It's calculated as: \( A = Z + N \) where \( N \) is the number of neutrons.
  • Unlike the atomic number, the mass number can vary even for atoms of the same element.
This variation leads to the concept of isotopes. Mass number is not fixed because atoms of the same element can have different numbers of neutrons, resulting in isotopes. Knowing the mass number helps chemists differentiate between these isotopes.
Isotopes
Isotopes are variants of a particular chemical element that, while having the same atomic number \( Z \), have different mass numbers \( A \). This means they have different numbers of neutrons.
For example, carbon has two stable isotopes: \( ^{12}\text{C} \) and \( ^{13}\text{C} \). Both have 6 protons, but \( ^{12}\text{C} \) has 6 neutrons, while \( ^{13}\text{C} \) has 7 neutrons.
  • Isotopes of an element have similar chemical properties because they have the same number of electrons.
  • Physical properties, like mass and stability, can vary between different isotopes.
Understanding isotopes is crucial for fields like chemistry and physics where isotope identification plays a key role in nuclear reactions, medical imaging, and radiometric dating.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

One of the promising reactions for a controlled fusion reactor consumes deuterium \(\left({ }^{2} \mathrm{H}\right)\) and tritium \(\left({ }^{3} \mathrm{H}\right)\) in the reaction $$ \begin{array}{cccc} { }_{1}^{2} \mathrm{H}+{ }_{1}^{3} \mathrm{H} & { }_{2}^{4} \mathrm{He}+{ }_{0}^{1} \mathrm{n} \\ 2.0140 & 3.0161 & 4.0026 & 1.008665 \end{array} $$ The atomic mass of each particle is given below the equation. Calculate the energy released by this fusion reaction per gram of helium formed, and compare it with the energy generated by the fission of \(1 \mathrm{~g}^{235} \mathrm{U}\left(8 \times 10^{7} \mathrm{~kJ} / \mathrm{g}\right)\).

Explain why most fission products formed in a nuclear reactor decay by beta emission rather than undergoing another kind of nuclear decay.

Identify the missing particles by balancing the mass and atomic numbers in each of the following nuclear decay equations. (a) \({ }_{94}^{242} \mathrm{Pu} \longrightarrow{ }_{2}^{4} \alpha+\) (b) \(\longrightarrow \underset{16}{32} \mathrm{~S}+{ }_{-1}^{0} \beta\) (c) \({ }^{252} \mathrm{Cf}+\longrightarrow{ }_{98}^{1} \mathrm{n}+{ }_{103}^{259} \mathrm{Lr}\) (d) \({ }_{26}^{55} \mathrm{Fe}+\) \(\longrightarrow \frac{55}{25} \mathrm{Mn}\) (e) \({ }_{8}^{15} \bigcirc \longrightarrow\) \(+\begin{array}{r}0 \\ +1\end{array} \beta\)

A person's exposure to radiation can depend greatly on occupation. List several occupations that may result in an exposure to radiation greater than the average exposure of the U.S. population. Explain your choices.

The \({ }_{6}^{14} \mathrm{C}\) activity of an artifact from a burial site was \(8.6 / \mathrm{min}\) per gram carbon. The half-life of \({ }_{6}^{14} \mathrm{C}\) is 5730 years, and the current \({ }_{6}^{14} \mathrm{C}\) activity is 15.3 disintegrations per minute per gram of carbon. How old is the artifact?
See all solutions

Recommended explanations on Chemistry Textbooks

The Earths Atmosphere

Read Explanation

Inorganic Chemistry

Read Explanation

Physical Chemistry

Read Explanation

Making Measurements

Read Explanation

Nuclear Chemistry

Read Explanation

Ionic and Molecular Compounds

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.