refer to the periodic table of the elements to help you answer this question. if the number of protons in an electrically neutral atom is 92 and its mass number is 238, what is the name of that element, its number of electrons, and number of neutrons?

get refer to the periodic table of the elements to help you answer this question. if the number of protons in an electrically neutral atom is 92 and its mass number is 238, what is the name of that element, its number of electrons, and number of neutrons? from EN Bilgi.

3.3 Atomic Structure and Symbolism – CHEM 1114 – Introduction to Chemistry

Key Equations

Exercises

1. Write the symbol for each of the following ions:

a) the ion with a 1+ charge, atomic number 55, and mass number 133

b) the ion with 54 electrons, 53 protons, and 74 neutrons

c) the ion with atomic number 15, mass number 31, and a 3− charge

d) the ion with 24 electrons, 30 neutrons, and a 3+ charge

a) Pick any one of the first 10 elements that you would like to build and state its symbol.

b) Drag protons, neutrons, and electrons onto the atom template to make an atom of your element.

State the numbers of protons, neutrons, and electrons in your atom, as well as the net charge and mass number.

c) Click on “Net Charge” and “Mass Number,” check your answers to (b), and correct, if needed.

d) Predict whether your atom will be stable or unstable. State your reasoning.

e) Check the “Stable/Unstable” box. Was your answer to (d) correct? If not, first predict what you can do to make a stable atom of your element, and then do it and see if it works. Explain your reasoning.

a) Drag protons, neutrons, and electrons onto the atom template to make a neutral atom of Lithium-6 and give the isotope symbol for this atom.

b) Now remove one electron to make an ion and give the symbol for the ion you have created.

4. The following are properties of isotopes of two elements that are essential in our diet. Determine the number of protons, neutrons and electrons in each and name them.

a) atomic number 26, mass number 58, charge of 2+

b) atomic number 53, mass number 127, charge of 1−

5. Give the number of protons, electrons, and neutrons in neutral atoms of each of the following isotopes:

a) 73Li${}_3^7\text{Li}$

b) 12552Te${}_{52}^{125}\text{Te}$

c) 10947Ag${}_{47}^{109}\text{Ag}$

d) 157N${}_7^{15}\text{N}$

e) 3115P${}_{15}^{31}\text{P}$

6. Average atomic masses listed by IUPAC are based on a study of experimental results. Bromine has two isotopes ⁷⁹Br and ⁸¹Br, whose masses (78.9183 and 80.9163 amu) and abundances (50.69% and 49.31%) were determined in earlier experiments. Calculate the average atomic mass of bromine based on these experiments.

7. The average atomic masses of some elements may vary, depending upon the sources of their ores. Naturally occurring boron consists of two isotopes with accurately known masses (¹⁰B, 10.0129 amu and ¹¹B, 11.0931 amu). The average atomic mass of boron can vary from 10.807 to 10.819, depending on whether the mineral source is from Turkey or the United States. Calculate the percent abundances leading to the two values of the average atomic masses of boron from these two countries.

8. Explain Dalton’s atomic theory.

9. Which is larger, a proton or an electron?

10. Which is larger, a neutron or an electron?

11. What are the charges for each of the three subatomic particles?

12. Where is most of the mass of an atom located?

13. Sketch a diagram of a boron atom, which has five protons and six neutrons in its nucleus.

16. What is the difference between deuterium and tritium?

17. Which pair represents isotopes?

a)        b)  ₂₆F and ₂₅M        c)  ₁₄S and ₁₅P

18.  Which pair represents isotopes?₂₀ and ₁₉K      b)  ₂₆F and ₂₇F          ₉₂ and ₉₂U     d) 147N${}_7^{14}\text{N}$ and 148N${}_8^{14}\text{N}$ 

19.  Give complete symbols of each atom, including the atomic number and the mass number.

a)  an oxygen atom with 8 protons and 8 neutrons

b)  a potassium atom with 19 protons and 20 neutrons

c)  a lithium atom with 3 protons and 4 neutrons

a)  a magnesium atom with 12 protons and 12 neutrons

b)  a magnesium atom with 12 protons and 13 neutrons

c)  a xenon atom with 54 protons and 77 neutrons

a)  sodium     b)  argon     c)  nitrogen     d)  radon

a)  silver     b)  gold      c)  mercury      d)  iodine

a)  Si      b)  Mn      c)  Fe      d)  Cr

a)  F      b)  Cl      c)  Br      d)  I

27. Determine the atomic mass of each element, given the isotopic composition.

a)  lithium, which is 92.4% lithium-7 (mass 7.016 u) and 7.60% lithium-6 (mass 6.015 u)

b)  oxygen, which is 99.76% oxygen-16 (mass 15.995 u), 0.038% oxygen-17 (mass 16.999 u), and 0.205% oxygen-18 (mass 17.999 u)

1. (a) ¹³³Cs⁺; (b) ¹²⁷I⁻; (c) ³¹P³⁻; (d) ⁵⁷Co³⁺

2. (a) Carbon-12, ¹²C; (b) This atom contains six protons and six neutrons. There are six electrons in a neutral ¹²C atom. The net charge of such a neutral atom is zero, and the mass number is 12. (c) The preceding answers are correct. (d) The atom will be stable since C-12 is a stable isotope of carbon. (e) The preceding answer is correct. Other answers for this exercise are possible if a different element of isotope is chosen.

3. (a) Lithium-6 contains three protons, three neutrons, and three electrons. The isotope symbol is ⁶Li or 63Li${}_3^6\text{Li}$. (b) ⁶Li⁺ or 63Li+${}_3^6{\text{Li}}^{+}$

4. (a) Iron, 26 protons, 24 electrons, and 32 neutrons; (b) iodine, 53 protons, 54 electrons, and 74 neutrons

5. (a) 3 protons, 3 electrons, 4 neutrons; (b) 52 protons, 52 electrons, 73 neutrons; (c) 47 protons, 47 electrons, 62 neutrons; (d) 7 protons, 7 electrons, 8 neutrons; (e) 15 protons, 15 electrons, 16 neutrons

6. 79.904 amu

7. Turkey source: 0.2649 (of 10.0129 amu isotope); US source: 0.2537 (of 10.0129 amu isotope)

8. All matter is composed of atoms; atoms of the same element are the same, and atoms of different elements are different; atoms combine in whole-number ratios to form compounds.

9. A proton is larger than an electron.
10. A neutron is larger than an electron.
11. proton: 1+; electron: 1−; neutron: 0
12.  Most of the mass of an atom is located in the nucleus.

19.  a) 168O${}_8^{16}\text{O}$      b)  3919K${}_{19}^{39}\text{K}$      c)  73Li${}_3^7\text{Li}$

a)  2412Mg${}_{12}^{24}\text{Mg}$      b)  2512Mg${}_{12}^{25}\text{Mg}$      c)  13154Xe${}_{54}^{131}\text{Xe}$

21.   24195Am${}_{95}^{241}\text{Am}$

23.  a)  Na     b)  Ar     c)  N     d)  Rn

24.  a)  Ag     b)  Au      c)  Hg      d)  I

25.  a)  silicon      b)  manganese      c)  iron      d)  chromium

26.  a)  fluorine      b)  chlorine      c)  bromine      d)  iodine

27.  a)  6.940 u     b)  16.000 u

Glossary

atomic mass unit (amu): (also, unified atomic mass unit, u, or Dalton, Da) unit of mass equal to 112$\frac{1}{12}$ of the mass of a ¹²C atom

fundamental unit of charge: (also called the elementary charge) equals the magnitude of the charge of an electron (e) with e = 1.602 × 10⁻¹⁹ C

Source : pressbooks.bccampus.ca