Questions and Answers
Why does it make sense that if an atom loses electrons, it is left with a positive charge?
If an atom loses an electron, then it becomes positively charged because the total charge of the electrons no longer balance the total charge of the protons to form a neutral particle.
Why is an atom electrically neutral?
Because the number of protons equals the number of electrons.
What does the atomic number of each atom represent?
The atomic number of an element represents the number of protons in that element.
How many protons are in the nuclei of Phosphorus?
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How many protons are in the nuclei of Molybdenum?
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How many protons are in the nuclei of Aluminum?
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What's the difference between the mass number and the atomic number of an atom?
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Name two ways that isotopes of an element can differ.
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What characteristics of cathode rays led Thomson to conclude that the rays consisted of negatively charged particles?
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What's the same between carbon 12 and carbon 13?
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What's different between carbon 12 and carbon 13?
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How do you find the number of neutrons?
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How do you find the number of protons/electrons?
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How do you find the mass number?
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What is the definition of a group?
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What is a period?
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What is an Atomic Mass Unit (AMU)?
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The number of ______ in the nucleus of an atom is the atomic _______ of that element.
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The total number of ______ and neutrons in an atom is the mass number.
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Atoms of the same element are identical in most respects, but they can differ in the number of ______ in the nucleus.
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Atoms that have the same number of protons but different mass numbers are called ______.
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The ______ of an element is the weighted average of the masses of the isotopes of that element.
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Each of the three known isotopes of hydrogen has ______ protons in its nucleus.
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Dalton's Atomic Theory included the idea that the atoms of different elements can chemically combine in ______ ratios.
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An atom is the smallest particle of an element that retains its identity in a ______.
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______ are subatomic particles with a negative charge.
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The nucleus of an atom is composed of ______ and protons.
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A neutron has no charge, but its mass is almost the same as a ______.
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The number of protons in an atom is called its ______ number.
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Isotopes of an element have different numbers of neutrons. They also have different ______ numbers.
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The mass number of an element with 14 electrons and 16 neutrons = ?
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What are the horizontal rows of the periodic table called?
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The elements in the periodic table are listed in order of increasing what?
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What are the vertical columns of the periodic table called?
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Atoms that have the same number of protons but different numbers of neutrons are called what?
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The number of neutrons can be calculated by:
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Relative atomic masses are expressed in what?
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Does an atom of nitrogen always have 7 protons and 7 neutrons?
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How do you find the atomic number?
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What did we find out with Rutherford's gold experiment?
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How do you find the mass number?
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Study Notes
Atomic Structure and Charge
- An atom becomes positively charged when it loses electrons since the balance between protons and electrons is disrupted.
- Atoms are electrically neutral due to an equal number of protons and electrons.
Atomic Number and Protons
- The atomic number indicates the number of protons present in an atom.
- Phosphorus has an atomic number of 15, indicating 15 protons.
- Molybdenum has an atomic number of 42, indicating 42 protons.
- Aluminum has an atomic number of 13, indicating 13 protons.
Mass Number vs. Atomic Number
- The mass number is the sum of protons and neutrons in an atom, while the atomic number only counts protons.
Isotopes
- Isotopes vary in mass numbers, atomic masses, the number of neutrons, and relative abundance.
- Carbon-12 and Carbon-13 have the same number of protons but differ in neutrons.
Calculating Particles
- To find the number of neutrons: Mass Number - Atomic Number.
- To determine protons or electrons, refer to the atomic number.
- The mass number is calculated as protons + neutrons.
Periodic Table Organization
- A group refers to a vertical column of elements, while a period refers to a horizontal row.
- Atomic Mass Unit (AMU) is defined as 1/12 the mass of a carbon-12 atom.
- Elements are arranged in the periodic table in order of increasing atomic number.
Subatomic Particles
- Electrons are negatively charged subatomic particles.
- The nucleus comprises protons and neutrons, with neutrons having no charge and a mass similar to protons.
Fundamental Concepts
- Dalton's Atomic Theory states that atoms can combine in simple whole-number ratios.
- Atoms retain identity during chemical reactions.
Additional Concepts
- Atoms of the same element are generally identical in structure but may vary in neutron count.
- Relative atomic masses are measured in AMUs.
- Rutherford's gold foil experiment concluded that atoms are primarily empty space.
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Description
This quiz offers a comprehensive review of Chapter 4 in chemistry through flashcards. It covers fundamental concepts, including atomic structure and electrical neutrality. Test your understanding of how electrons and protons interact to define atomic charge.