Model Textbook of Chemistry - 180 Flashcards (Video Notes)

180 flashcards covering key concepts from the lecture notes on Nature of Science in Chemistry, Matter, Atomic Structure, Periodic Table and Periodicity, and Chemical Bonding. Each flashcard is a QUESTION_AND_ANSWER pair in English.

What is the definition of chemistry?

Chemistry is the science that studies matter, its composition, structure, properties, behavior, and changes, including interactions with energy.

Name a branch of chemistry that deals with substances containing carbon (excluding carbonates, bicarbonates, oxides, and carbides).

Organic Chemistry.

What does Inorganic Chemistry study?

Elements and their compounds except organic compounds.

What is Physical Chemistry about?

The laws and theories that explain the structure and changes of matter.

What is Analytical Chemistry?

Methods and instruments for determining the composition and properties of matter.

What is Biochemistry?

The branch of chemistry that studies chemical changes in living organisms.

What does Environmental Chemistry study?

Chemical substances that pollute the environment and their effects on humans.

What is Industrial Chemistry?

The branch dealing with the large-scale production of chemical substances.

What is Medicinal Chemistry?

The study of interactions between drugs and biological targets and the development of new medicines.

What is Polymer Chemistry?

Study of polymers, their types, properties, uses, and polymerizations.

What is Geochemistry?

The study of chemical composition, distribution, and transformation of elements in the Earth's crust.

What is Nuclear Chemistry?

Chemistry dealing with changes in atomic nuclei and related phenomena.

What is Astrochemistry?

Chemistry that studies chemical processes in astronomical environments.

What is Green Chemistry?

Chemistry that designs products and processes to minimize hazardous substances and pollution.

How can you differentiate science, technology, and engineering?

Science is the systematic study of the natural world; technology applies scientific knowledge for practical use; engineering applies science and math to design and build systems and solutions.

Give an example of how chemistry relates to rusting.

Rusting investigates chemical reactions between iron, water, and oxygen to form iron oxides.

What is an example of applying chemistry to harness solar energy?

Studying photovoltaic principles to convert sunlight into electricity and designing solar panels.

What is an example of applying chemistry to water filtration?

Designing filtration and disinfection processes to supply clean drinking water.

What organic process is involved in making French fries from an organic chemistry perspective?

Oil contains carbohydrates and other organics; scientists study carbohydrates to understand their role in cooking and processing oils.

What is the first-ever core curriculum reference in the Preface about?

Pakistan's 2022-2023 national core curriculum introducing a standard for schooling.

What is the unit that introduces matter in Unit 2?

Matter, its states, and properties.

How is matter defined in Unit 2?

Anything that has mass and occupies space.

What are the four states of matter listed in Unit 2?

Gas, Liquid, Solid, Plasma.

What is a liquid crystal state?

A cloudy liquid state with some properties of solids and liquids within a certain temperature range.

What is Bose-Einstein Condensate (BEC)?

A state of matter at temperatures very close to absolute zero where atoms act as a single quantum entity.

What is allotropy?

The property of an element to exist in different physical forms in the same state (e.g., carbon as diamond, graphite, buckyballs).

What is a pure substance?

A substance with a uniform composition, either an element or a compound.

What is a compound?

A substance formed when two or more different elements chemically combine.

What is a mixture?

A physical combination of two or more substances that are not chemically bonded.

What is a homogeneous mixture?

A mixture where the composition is uniform throughout (solutions, colloids).

What is a heterogeneous mixture?

A mixture with visibly different parts or phases (suspensions, emulsions, colloids).

What is a solute?

The substance that is dissolved in a solvent.

What is a solvent?

The substance in which the solute dissolves.

What is a solution?

A homogeneous mixture of two or more substances where one is dissolved in the other.

What size are solute particles in a true solution?

Microscopic, usually less than 1 nm in diameter.

What is an aqueous solution?

A solution in which the solvent is water.

What is the universal solvent in many aqueous solutions?

Water.

What is a saturated solution?

A solution that contains the maximum amount of solute at a given temperature.

What is an unsaturated solution?

A solution that can still dissolve more solute at a given temperature.

What is a supersaturated solution?

A solution that contains more solute than a saturated solution at a given temperature.

What is the difference between dilute and concentrated solutions?

Dilute solutions have relatively little solute; concentrated solutions have a large amount of solute.

What is solubility?

The maximum amount of solute that dissolves in a solvent at a given temperature.

How does temperature affect solubility?

Solubility can increase or decrease with temperature depending on the solute (e.g., KNO3 increases, Ca(OH)2 decreases with temperature).

What are aqueous solutions often used for in labs?

They are common in laboratories for dissolving solutes and performing reactions.

What is a colloid?

A heterogeneous mixture with particles between 1 and 1000 nm that scatter light (Tyndall effect) and don’t settle quickly.

What is a suspension?

A heterogeneous mixture where solid particles are dispersed in a liquid and can settle out.

What is the Tyndall effect?

Scattering of light by colloidal particles, distinguishing colloids from true solutions.

Give examples of colloids.

Starch, albumin, milk, ink, toothpaste, blood.

Give examples of suspensions.

Chalk in water, paints, milk of magnesia.

What is the meaning of a solution’s stability?

A true solution remains uniformly mixed and does not separate.

What is an allotrope?

Different structural forms of the same element (e.g., carbon as diamond, graphite, buckyballs).

Which carbon allotropes are soft lubricants with layered structures?

Graphite.

Which carbon allotrope is the hardest natural substance?

Diamond.

What is the role of isotopes in atomic mass?

Isotopes have the same number of protons but different numbers of neutrons, affecting atomic mass.

What is a proton?

Positively charged subatomic particle in the nucleus with approximately 1 amu mass.

What is a neutron?

Neutral subatomic particle in the nucleus with approximately 1 amu mass.

What is an electron?

Negatively charged subatomic particle in electron shells with negligible mass relative to protons and neutrons.

Where are protons and neutrons located in an atom?

In the nucleus.

Where do electrons reside in an atom?

In shells (energy levels) surrounding the nucleus.

What holds protons and neutrons together in the nucleus?

The strong nuclear force.

What is an atomic model?

A conceptual representation to understand atomic structure, not a physical replica.

What is the nucleus’s charge?

Positive due to protons; neutrons are neutral.

What is the electron’s mass contribution to an atom’s mass?

Negligible compared to protons and neutrons.

What is the Rutherford atomic model key conclusion?

Most of an atom’s volume is empty space; a dense positively charged nucleus exists at the center.

What did Bohr’s model introduce that Rutherford’s did not fully explain?

Quantized orbits (energy levels) and hydrogen spectral lines.

What is the quantum mechanical model?

The current model treating electrons as waves with probabilistic orbitals rather than fixed paths.

What is the Heisenberg Uncertainty Principle?

It is impossible to know simultaneously the exact position and exact future path of an electron.

Who proposed the wave nature of electrons?

Louis de Broglie.

What did Davisson and Germer confirm in 1927?

That electrons exhibit wave-like behavior.

What is an orbital in the quantum model?

A region in space where an electron is likely to be found.

What is Z in atomic notation?

The atomic (proton) number; it defines element identity.

What is A in atomic notation?

The nucleon (mass) number, sum of protons and neutrons.

What is RAM (Relative Atomic Mass)?

The average mass of an element’s isotopes relative to 1/12th of the mass of carbon-12.

What is amu?

Atomic Mass Unit; defined as 1/12 of the mass of a carbon-12 atom.

What is an isotope?

Atoms of the same element with the same number of protons but different neutrons.

Do isotopes have different chemical properties?

No; isotopes have similar chemical properties but different physical properties due to mass differences.

What is carbon dating?

Using carbon-14 to estimate the age of carbon-containing samples.

What is a cation?

A positively charged ion formed when an atom loses electrons.

What is an anion?

A negatively charged ion formed when an atom gains electrons.

What determines an element’s identity in the periodic table?

Its proton (atomic) number Z.

What is nucleon number?

The total number of protons and neutrons (mass number A).

What are isotopes’ chemical properties like?

Chemically similar because they have the same number of protons; mass-related properties differ.

What is the Aufbau principle?

Electrons fill the lowest-energy sub-shells first (1s, 2s, 2p, 3s, 3p, …).

What are sub-shells and their capacities: s, p, d, f?

s: 2; p: 6; d: 10; f: 14 electrons.

What is the general symbol notation for an atom/ion?

Element symbol with mass number as a superscript, atomic number as a subscript, and charge as a superscript.

What determines an element’s group when in the s-block?

The group equals the number of valence electrons.

What determines an element’s group when in the p-block?

Group = (valence electrons) + 10.

What is a halogen?

Group 17 elements; highly reactive non-metals that form -1 ions.

What is a noble gas?

Group 18 elements with complete outer electron shells and low reactivity.

What is a transition element?

Elements in the d-block with variable oxidation states and catalytic properties.

What is the result of radioactive decay?

The nucleus changes, possibly altering the element’s identity if protons change.

What is the hydrogen-1 isotope called?

Protium.

What is the heavier isotope of hydrogen called?

Deuterium (hydrogen-2) and Tritium (hydrogen-3); Tritium is radioactive.

What are the isotopes of carbon?

12C, 13C, 14C.

What is the natural abundance of carbon isotopes?

12C about 98.8%, 13C about 1.1%, 14C about 0.009%.

What is the consequence of isotopes on molecular mass vs chemical properties?

Isotopes change molecular mass but not chemical properties.

What is the charge of a proton, neutron, and electron relative to each other?

+1 for proton, 0 for neutron, -1 for electron.

Define mass number (A).

Sum of protons and neutrons in the nucleus.

Define atomic number (Z).

Number of protons in the nucleus; determines element identity.

What is a cation formation example with Na?

Na loses 1 electron to form Na+.