Lesson 2 We Are All Made of Star Stuff (Formation of the Heavy Elements)Simple ABbieC
Content: How the elements found in the universe were formed
Content Standard:
At the end of the lesson, you will be able to demonstrate an understanding of:
the formation of the elements during the Big Bang and during stellar evolution
the distribution of the chemical elements and the isotopes in the universe
Learning Competencies:
At the end of the lesson,
Give evidence for and describe the formation of heavier elements during star formation and evolution (S11/12PS-IIIa-2)
Write the nuclear fusion reactions that take place in stars that lead to the formation of new elements (S11/12PS-IIIa-3)
Describe how elements heavier than iron are formed (S11/12PSIIIa-b-4))
Lesson 1 In the Beginning (Big Bang Theory and the Formation of Light Elements)Simple ABbieC
Content: How the Elements Found in the Universe were Formed
Content Standard:
The learners demonstrate an understanding of:
• the formation of the elements during the Big Bang and during stellar evolution
Learning Competency
The learners:
• give evidence for and explain the formation of the light elements in the Big Bang theory (S11/12PS-IIIa-1)
Summary
• The big bang theory explains how the elements were initially formed the formation of different elements involved many nuclear reactions, including fusion fission and radioactive decay
• There are three cosmic stages through which specific groups of elements were formed.
(1) The big bang nucleosynthesis formed the light elements(H, He, and Li).
(2) Stellar formation and evolution formed the elements heavier than Be to Fe.
(3) Stellar explosion , or supernova, formed the elements heavier than Fe.
• Atoms are the smallest unit of matter that have all the properties of an element. They composed of smaller subatomic particles as protons, neutrons, and electrons. Protons have positive charge, neutrons are electrically neutral; and electrons have a negative charge.
• The nucleus, which takes the central region of an atom, is comprised of protons and neutrons, electrons move around the nucleus.
• The atomic number (Z) indicates the number of protons in an atom. In a neutral atom, number of protons is equal to the number of electrons. The atomic mass (A) is equal to the sum of the number of protons and neutrons.
• Isotopes refer to atoms with the same atomic number but different atomic masses.
• Ions, which are positively or negatively charged particles, have the same number of protons in different number of electrons.
Lesson 2 We Are All Made of Star Stuff (Formation of the Heavy Elements)Simple ABbieC
Content: How the elements found in the universe were formed
Content Standard:
At the end of the lesson, you will be able to demonstrate an understanding of:
the formation of the elements during the Big Bang and during stellar evolution
the distribution of the chemical elements and the isotopes in the universe
Learning Competencies:
At the end of the lesson,
Give evidence for and describe the formation of heavier elements during star formation and evolution (S11/12PS-IIIa-2)
Write the nuclear fusion reactions that take place in stars that lead to the formation of new elements (S11/12PS-IIIa-3)
Describe how elements heavier than iron are formed (S11/12PSIIIa-b-4))
Lesson 1 In the Beginning (Big Bang Theory and the Formation of Light Elements)Simple ABbieC
Content: How the Elements Found in the Universe were Formed
Content Standard:
The learners demonstrate an understanding of:
• the formation of the elements during the Big Bang and during stellar evolution
Learning Competency
The learners:
• give evidence for and explain the formation of the light elements in the Big Bang theory (S11/12PS-IIIa-1)
Summary
• The big bang theory explains how the elements were initially formed the formation of different elements involved many nuclear reactions, including fusion fission and radioactive decay
• There are three cosmic stages through which specific groups of elements were formed.
(1) The big bang nucleosynthesis formed the light elements(H, He, and Li).
(2) Stellar formation and evolution formed the elements heavier than Be to Fe.
(3) Stellar explosion , or supernova, formed the elements heavier than Fe.
• Atoms are the smallest unit of matter that have all the properties of an element. They composed of smaller subatomic particles as protons, neutrons, and electrons. Protons have positive charge, neutrons are electrically neutral; and electrons have a negative charge.
• The nucleus, which takes the central region of an atom, is comprised of protons and neutrons, electrons move around the nucleus.
• The atomic number (Z) indicates the number of protons in an atom. In a neutral atom, number of protons is equal to the number of electrons. The atomic mass (A) is equal to the sum of the number of protons and neutrons.
• Isotopes refer to atoms with the same atomic number but different atomic masses.
• Ions, which are positively or negatively charged particles, have the same number of protons in different number of electrons.
Synthesis of the New Elements in the Laboratory Jhay Gonzales
The power point presentation is intended for reporting purposes. Various slides were not defined well and needs to be explained by the reporter during the discussion. The slide started in explaining the objective of the reporting. Explain what a periodic table is. Present the synthetic elements and how they were made. The nuclear reactions presented were only depicted by images and thus, needed to be researched.
Lesson 4 Not Indivisible (The Structure of the Atom)Simple ABbieC
Learning Competencies
At the end of the lesson, you will have to:
1. point out the main ideas in the discovery of the structure of the atom and its subatomic particles
2. cite the contributions of J.J. Thomson, Ernest Rutherford, Henry Moseley, and Niels Bohr to the understanding of the structure of the atom
3. describe the nuclear model of the atom and the location of its major components (protons, neutrons, and electrons)
Planet Earth and its properties necessary to support lifeSimple ABbieC
Department of Education | Senior High School
Topic: Planet Earth and its properties necessary to support life.
Learning Competency:
Earth and Life Science: Recognize the uniqueness of Earth, being the only planet in the Solar System with properties necessary to support life.
Earth Science (for STEM): Describe the characteristics of Earth that are necessary to support life.
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Lesson 3 Atomos, Aristotle and Alchemy (Chemistry Before Modern History)Simple ABbieC
Lesson 3 Atomos, Aristotle and Alchemy (Chemistry Before Modern History)
CONTENT:
How the idea of the atom, along with the idea of the elements evolved
CONTENT STANDARD
At the end of the lesson, you will have to describe:
1. how the concept of the atom evolved from Ancient Greek to the present; and
2. how the concept of the element evolved from Ancient Greek to the present
LEARNING COMPETENCIES
At the end of the lesson, you will have to:
1. describe the ideas of the Ancient Greeks on the atom (S11/12PS-IIIa-b-5)
2. describe the ideas of the Ancient Greeks on the elements (2 hours) (S11/12PS-IIIa-b-6)
3. describe the contributions of the alchemists to the science of chemistry (S11/12PS-IIIb-7)
Synthesis of the New Elements in the Laboratory Jhay Gonzales
The power point presentation is intended for reporting purposes. Various slides were not defined well and needs to be explained by the reporter during the discussion. The slide started in explaining the objective of the reporting. Explain what a periodic table is. Present the synthetic elements and how they were made. The nuclear reactions presented were only depicted by images and thus, needed to be researched.
Lesson 4 Not Indivisible (The Structure of the Atom)Simple ABbieC
Learning Competencies
At the end of the lesson, you will have to:
1. point out the main ideas in the discovery of the structure of the atom and its subatomic particles
2. cite the contributions of J.J. Thomson, Ernest Rutherford, Henry Moseley, and Niels Bohr to the understanding of the structure of the atom
3. describe the nuclear model of the atom and the location of its major components (protons, neutrons, and electrons)
Planet Earth and its properties necessary to support lifeSimple ABbieC
Department of Education | Senior High School
Topic: Planet Earth and its properties necessary to support life.
Learning Competency:
Earth and Life Science: Recognize the uniqueness of Earth, being the only planet in the Solar System with properties necessary to support life.
Earth Science (for STEM): Describe the characteristics of Earth that are necessary to support life.
Please LIKE / FOLLOW and SHARE my other social media accounts.
Facebook: https://www.facebook.com/Simple-ABbieC-131584525051378/
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Youtube:
http://tiny.cc/SimpleABbieC
-----------------------------------------------------------------------
Slideshare:
https://www.slideshare.net/AbbieMahinay
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Blogger:
https://simpleabbiec.blogspot.com/?m=1
Lesson 3 Atomos, Aristotle and Alchemy (Chemistry Before Modern History)Simple ABbieC
Lesson 3 Atomos, Aristotle and Alchemy (Chemistry Before Modern History)
CONTENT:
How the idea of the atom, along with the idea of the elements evolved
CONTENT STANDARD
At the end of the lesson, you will have to describe:
1. how the concept of the atom evolved from Ancient Greek to the present; and
2. how the concept of the element evolved from Ancient Greek to the present
LEARNING COMPETENCIES
At the end of the lesson, you will have to:
1. describe the ideas of the Ancient Greeks on the atom (S11/12PS-IIIa-b-5)
2. describe the ideas of the Ancient Greeks on the elements (2 hours) (S11/12PS-IIIa-b-6)
3. describe the contributions of the alchemists to the science of chemistry (S11/12PS-IIIb-7)
Experimental Questions 1- Which types of compounds have the strongest.docxtodd401
Experimental Questions 1. Which types of compounds have the strongest intermolecular forces? How can certain physical properties give an indication of the strength of intermolecular forces of compounds? 2. 3. Relate molecular polarity to the intermolecular forces of the molecule. 4. Relate intermolecular forces of the molecule to physical properties such as evaporation and viscosity.
Solution
1. The strongest intermolecular force is hydrogen bonding. Thus the compounds that can form H- bonds each other have the strongest intermolecular forces.
2. When intermolecular forces increases the molecules fells greater attraction among themselves. This means we have to supply more energy to separate them. This result in higher in the physical property. Thus if stronger intermolecular forces are existing we can expect that boiling point , melting point for that sample will increase. Again in case of freezing we have to restrict the movements of the molecules.Thus when stronger forces are there there are already some restriction in the movements and so freezing point is higher. In other words we can say that molecules where there is lower intermolecular forces we have to lower the temperature more to freeze it.
3. When polarity of the molecules increases this gives greater intermolecular forces and thus higher physical properties. This is because each molecular dipole allign themselves with others in such. a way that
(+)vely charged part attract the (-)vely charged part and this result long range intermolecular forces. This gives higher intermolecular forces.
4. Evaporation means escape of molecules from the liquis phase. When there is strong intermolecular force exists this means the molecules attract each other more. Thus escape from liquid phase is less. But when intermolecular force is weaker then molecules can escape easily. This means lower the intermolecular force higher the evaporation rate.
Again Viscosity is the resistance of a liquid to flow. When attraction is more among the molecules they resist the flow of other molecules. This implies higher viscosity. For example ethanol , CH3CH2OH, has the viscosity 1.07 mPa.s and ethylene glycol, HOCH2CH2OH , has 16.2 mPa.s. We can see that in case of ethanol there is only one OH group. But in case of ethylene glycol there is 2 OH group that can form strong H bonding. This results higher attraction among ethylene glycol moecules and so higher viscosity.
.
General Chemistry 2_IMF and Properties of Liquids.pptxKristelJoySomera
This power point presentation focuses on the different intermolecular forces that binds molecules in order for solids to remain solids or liquid to remain liquids. This presentation also presents the different properties of liquid that can be explained through the concept of intermolecular forces. It also contains simple activities to test the understanding of the learners on the lesson.
The Kinetic Molecular Model and Intermolecular Forces of Attraction in Matter is one of the important topic in Grade 12, General Chemistry 2 subject. In here, it includes topics that discusses theory of solids and liquids, the different intermolecular and intramolecular forces such as covalent and ionic bonds, dipole- dipole, hydrogen bonds, london dispersion,
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
2. OBJECTIVES
After going through this module, you are expected to:
1.Define solubility, miscibility and polarity;
2.Identify the different types of intermolecular forces of attraction
3.Explain how polarity of molecules related to its properties
3. Polarity, Solubility, and Miscibility
Polarity is a separation of electric charge leading to a
molecule or its chemical groups having an electric
dipole moment, with a negatively charged end and a
positively charged end. Polar molecules must contain one
or more polar bonds due to a difference in
electronegativity between the bonded atoms.
Solubility is defined as the ability of a solid substance to
be dissolved in a given amount of solvent.
Miscibility is the ability of the two liquids to combine or
mix in all proportions, creating a homogenous mixture.
4. What chemistry concept did you used in answering the question above? If you
answered polarity of molecules, then you are on the right track. Great job!
Benzene and chloroform are both nonpolar compounds while water and vinegar
are both polar compounds, thus they are miscible to each other. However, the
rest is a combination of polar and nonpolar molecules and therefore will not
mix and instead will form two layers even if shake nor carefully stirred.
The general rule to remember
about the solubility and miscibility
of molecular compounds can be
summarized in a phrase, “like
dissolves like” or “like mixes with
like”. This means that polar
substances will only be dissolved or
mixed with polar substances while
nonpolar substances will be soluble
or miscible with another nonpolar
substance.
Now I want you to try the exercises
below in order to assess how much
you have understood the solubility
(and miscibility) rule of substances
in relation to their polarity.
Which of the following substances
below will most likely mix with
each other?
a. water (H2O) and chloroform
(CHCl)
b. benzene (C6H6) and chloroform
(CHCl3)
c. water (H2O) and vinegar
(CH3COOH)
d. acetone (C3H6O) and toluene
(C6H5CH3)
e. carbon tetrachloride (CCl4) and
water(H2O)
5. B. Bond Strength and Physical Properties
of Covalent Compound
From the previous module, you learned the intramolecular forces of
attraction, the attractive force that binds atoms together. In this
module, you will learn another type of attractive force, the
intermolecular forces of attraction (IMFA) which exists between
molecules.
1.There are several types of IMFA and below they are arranged from
STRONGEST to WEAKEST. Ion-dipole →H-bonding→dipole-
dipole→dipole-induced dipole→London forces of attraction.
2. The strength of IMFA greatly affects the physical properties of
substances such as boiling point, melting point, vapor pressure,
surface tension, etc.
6. Table 1: shows the comparison of the various types of IMFA
while table 2 shows the physical properties of polar and
nonpolar molecules as affected by the type of IMFA present.
8. Let us define the physical properties of
substance:
A. Boiling point: temperature at which the vapor pressure and atmospheric
pressure of a liquid substance are equal.
B. Melting point: temperature at which solid becomes liquid. At this point, the
solid and liquid phases exist in equilibrium.
C. Surface tension: energy needed to increase the surface area by a unit amount;
D. Viscosity: the resistance of the liquid to flow.
E. Vapor Pressure: pressure exerted by a substance in its gaseous state.
F. Volatility: measures the rate at which a substance vaporizes(changes from liquid
to gas)
In the simplest sense, boiling point, melting point, viscosity and surface tension
increase as the strength of intermolecular forces increases. On the other hand,
vapor pressure and volatility decrease with increasing strength of IMFA. London
dispersion forces increase as the molecular mass of a substance increases. Unlike
in H-bonding, as the molar mass increases, the boiling point, melting point,
viscosity and surface tension decrease.
