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A-Level Chemistry Tuition Singapore/H2 Chemistry Tuition/JC Chemistry Tutor

Chemical Equilibrium – Concepts

1. Entropy (S) measures the degree of disorder in a system. The entropy of a system increases when the matter or energy in the system becomes more random in its arrangement. A system that has a high degree of disorder/randomness is said to have a large entropy. Gases have the highest entropy followed by liquids and solids.

2. The Gibbs Free Energy change, G, is the limiting maximum useful work that can be obtained from a reaction, at constant pressure. When G 0, the reaction is spontaneous.
Ecell = Ecathode – Eanode

5. Dynamic Equilibrium refers to a reversible reaction in which the forward and the backward reactions are taking place at the same rate and concentrations of reactants and product are constant.

6. Le Chatelier’s Principle states that if a system in equilibrium is subjected to a change which disturbs the equilibrium, the system will respond in such a manner as to reduce or counteract the effect of the change.

Industrial application:
Haber Process: 450 oC – 500 oC, 200 atm – 300 atm

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A-Level Mathematics Tuition Singapore/JC Maths/H2 Math Tuition and Tutor

Hi A-Level/H2 Math Students

J1 – Teaching Vectors 2

J2 – Revising Series & Sequence, Mathematical Induction, Relation & Recurrence, AP & GP with Practice Exam Papers

From A Level Math Tutors

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A-Level Physics Tuition Singapore/H2 Physics Tuition/JC Physics Tutor

Hi A-level/H2/JC Physics Tuition students

Definitions – Electric Field

1. Electric Field
An electric field is a region of space in which an electric force is experienced by a stationary electric charge placed at any point within the region.

2. Coulomb‟s Law
The magnitude of the electrostatic force between two point electric charges is directly proportional to the product of the magnitudes of the charges and inversely proportional to the square of their separation.

3. Electric Field Strength
The electric field strength (E) at a point in an electric field is defined as the electric force per unit positive charge experienced by a stationary charge placed at that point.

3. Electric Potential Energy
The electric potential energy at a point in an electric field is the work done by an external agent in bringing a point charge from infinity to that point. The potential energy at infinity is assigned a value of zero.

4. Electric Potential
The electric potential at a point in an electric field is the work done by an external agent per unit positive charge in bringing a point charge from infinity to that point. The potential at infinity is assigned a value of zero.

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O Level Chemistry Tuition Singapore/Chemistry O Level Tuition/Tutor

Experimental Techniques – Key Points

1. Fractional distillation is used to separate a mixture of liquids with different boiling points

2. The starting line in paper chromatography should be drawn with pencil and not ink. Ink contains dyes that will dissolve in the solvent.

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O-Level Singapore/O-Level/Physics and Chemistry Tuition/Physics Tutor

Key Points – Dynamics

1. In solving kinematics questions. We can define motion to the right is positive or negative.
All vectors quantities example displacement, velocity and acceleration in that direction will be positive.

2. A ball thrown upwards will experience a constant acceleration of g during the upward and downward motion with air resistance neglected.

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O-Level Singapore/O-Level/Pure Physics Tuition/Physics Tutor

Key Points – Dynamics

1. In solving kinematics questions. We can define motion to the right is positive or negative.
All vectors quantities example displacement, velocity and acceleration in that direction will be positive.

2. A ball thrown upwards will experience a constant acceleration of g during the upward and downward motion with air resistance neglected.

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O Level E Maths Tuition Singapore/Tuition O Level E Maths/Tutor

S3 – Teaching geometrical properties of angles, angle properties of polygon and symmetry.

S4 – Revising frequency distribution, histograms, Mean, median and mode and practice P2 prelim question

From O-Level Elementary Mathematics Singapore Tutor

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O-Level Additional Mathematics Tuition Singapore

S3 – Teaching Logarithms

S4 – Practice Exam questions focusing on Equations and Inequalities

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A Level GP/General Paper Tuition Singapore

Science Doesn’t Kill People … People Kill People

Science is the organized systematic pursuit of knowledge. The purposes of science are to explain and manipulate the physical world. Scientific discoveries have greatly aided mankind and have allowed us to manipulate nature to our benefit. A common concern is uncertainty over where science will lead us next. Many scientific discoveries are “irreversible”; once you have them you cannot go back. Therefore it is important to investigate where science is “taking” us so that we can be prepared. At issue as well is the objectivity of science; if science is not objective, then perhaps it can lead us to bad crises or can be steered to good solutions. Because of its potency, like the analogy of a child with a gun, science must be balanced with social responsibility. Despite the fears about science, the overall goal of science is to produce a better world. Scientists feel that by improving our knowledge of nature they can benefit mankind.

Science aims to improve our understanding of the world around us through two modes: explaining and manipulating the world around us. These two functions are not necessarily linked; quantum mechanics can accurately predict experimental outcomes, but it defies explanation. Based upon the two above-mentioned simple goals science would seem to be a relatively benign pastime, but the implications of science can be very potent. Defining the structure of an atom has given us the power to split the atom, producing helpful medical tools and destructive nuclear weapons. A better understanding of gravity has allowed us to put satellites into space allowing better global communication and navigation as well as clandestine spying operations. Because of the value of many scientific discoveries, it is no surprise that some of the most advanced research is funded by armies around the world.

Probably the most important scientific invention ever was agriculture. Agriculture allowed previously nomadic hunters to stay in one place and grow their own crops. This advancement allowed more leisure time, as less time was needed to find food, allowing the division of labour and creation of civilization. Since then, science has brought us sewer systems to reduce disease and allow even greater numbers of people to live together in densities never before possible. Not only are more people now able to live closer together, but their quality of life has increased as well. Life expectancies are rising and disease is becoming less common, seen especially in lower infant mortalities. While some animals have been ob¬served using primitive agricultural techniques, none are as advanced as humans. It is science which separates humans from animals. Science has allowed us to manipulate our environment to allow evolution and fulfilment of our intellectual potentials.

Why does one study science? Einstein described three sorts of motives for scientific research: enjoyment of intellectual power and accomplishment, satisfaction of practical purposes, and a sort of religious follow¬ing. While some might state that Einstein’s motives are out-dated, there still are visibly distinct motives present today. Molecular biologists, among others, have to choose between working in academia, a research park, industry, or even the military. These types of laboratories have very different characteristics and often have different goals as well. The existence of distinct goals in researching science implies that science cannot be truly objective. If science is to be unaffected by bias, it must be studied without bias, a possibility precluded by the studying of science for such ends as intellectual power and accomplishment. While it may vary by a scientist’s personal goals and area of interest, some goals and areas of interest are inconsistent with objective science. Scientists looking for fame might be more disposed to research more controversial issues. Research into aerodynamics or high power energy sources inevitably finds appli¬ca¬tions in military vehicles and weapons. Because the people who perform research have different values, they will inevitably select research which agrees with their values, imparting biases on the scope and possible results of their research.

More…….

A Level General Paper Admin

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A-Level Economics Tuition Singapore/H2/H1 Economics Tuition

Hi J1 H2 Economics Tuition Students

Micro Concept Lesson IV – Price Discrimination and
Allocative Inefficiency

1. Recap:
Characteristics affect behavior of firms, which in turn affects the outcomes/performance of firms.

2. Important Behaviors for the entire market structure syllabus

a) Output behavior
i. Marginalist Approach – produce up to the point where MC = MR

b) Pricing behavior/strategy
i. Price takers
ii. Price setters – P > MC
iii. Price setters – kinked demand theory
iv. Price setters – Price leadership model
v. Price setters – Cartel model
vi. Price setters – Price discrimination!

3. Important Outcomes/Performance
a) Types of Profits Earned by the Firm, in the short and long run
b) Whether it achieves allocative efficiency
c) Whether it achieves productive efficiency
d) Whether it achieves dynamic efficiency

4. WHAT TO MASTER FOR PD?
1) Technical knowledge: Definitions, types, graphs
2) Application knowledge:
i. What characteristics enable a firm to practice price discrimination?
ii. What kind of outcomes does price discrimination produce?

5. Almost everything you need to know about PD
a) General Definition: A pricing strategy/behavior that charges different prices to different group of consumers for the same good or service, for reasons not fully justifiable by costs.

b) General conditions required: differences in price elasticity of demand and barriers to switching sellers. In addition, the market structure should be oligopolistic or monopolistic in nature so that firms have sufficient market power for price setting.

c) General Types:
i. First Degree or Perfect Price Discrimination
 Firm separates market into individual consumer
 Charges the consumer the price they are willing and able to pay
 Firm extracts the entire consumer surplus that lies underneath the
demand curve and turns it into extra revenue or producer surplus
 The marginal revenue curve is now equal to the average revenue
curve.
 The firm subsequently adjusts their output in accordance to the
Marginalist principle.
 LINK TO CHARACTERISTICS: Firms who wish to succeed in practicing
this strategy needs to pay the cost of conducting market research to
obtain perfect knowledge regarding what each buyer is prepared to
pay.
 LINK TO OUTCOMES:
1) Output increases
2) Profits increases  increased ability to practice Dynamic E.
3) Consumer surplus falls to zero
4) AE Achieved Fully
5) Improved PE.

ii. Second Degree or Block Pricing
 Firms sell blocks of a product at different prices depending on the
quantity purchased.
 Prices fall as quantity purchased increases.
 Early-bird discounts (price discrimination by time)
 Outgoing calls by Singtel for calls from Singapore to Philippines

For complete comments please contact @9863 9633

From A Level Economic Tutor

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A-Level Economics Tuition Singapore/H2/H1 Economics Tuition

Hi J1 H1/H2 Economics Tuition Students

H1 Syllabus :
• Market Failure
o Public, Merit and Demerit Goods

H1 Learning Outcome :
• Explain the characteristics of public goods and why public goods are not provided by the market.
• Explain the characteristics of merit and demerit goods and why they result in under and over consumption.

Lecture 2 : Market Failure – Causes Part 2 (Merit, Demerit and Public Goods)

1. Merit Goods and Demerit Goods

Merit goods are private goods which the government feels people will under-consume without any form of government intervention. Under-consumption can result from imperfect information (i.e. consumers don’t know any better) or positive externalities. Examples include education and preventive healthcare.

Demerit goods are private goods which the government feels people will over-consume without any form of government intervention. For example, demerit goods such as cigarettes and street drugs, impose external costs on the society when consumed. Hence, the government will seek to reduce its consumption in order to reduce the negative externalities involved. Over-consumption of demerit goods can also arise from consumers’ lack of information.

! Stop and Think : Normative economics come into play in merit and demerit goods. Do you know why?

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From A Level Economic Tutor

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A-Level Chemistry Tuition Singapore/H2 Chemistry Tuition/JC Chemistry Tutor

Chemical Energetics – Defination

1. Hess’ law states that the change in enthalpy accompanying a reaction is independent of the path taken between the initial and final states.

2. The standard enthalpy change of reaction (Hrxn), is the enthalpy change when molar quantities of reactants (as specified by the chemical equation) react to form products under standard conditions 25C and 1 atm.

3. The standard enthalpy change of formation of a compound (Hf), is the enthalpy change when 1 mole of a pure compound in a specified state is formed from its constituent elements in their standard states, under standard conditions 25C and 1 atm.

4. The standard enthalpy change of combustion of a compound (Hc), is the enthalpy change when 1 mole of that compound is completely burnt in oxygen under standard conditions 25C and 1 atm.

5. The standard enthalpy change of neutralisation (Hneu), is the enthalpy change when an acid and a base react to form 1 mole of water under standard conditions 25C, and 1 atm.

6. The standard enthalpy change of atomisation of an element (Hatom ), is the enthalpy change when 1 mole of atoms in the gaseous state is formed from the element in its normal physical state under standard conditions 25C and 1 atm.

7. The bond dissociation energy of a bond is the energy required to break one mole of chemical bonds between two atoms in a molecule in the gaseous phase.

8. The first ionisation energy of an element (H1st I.E.), is the energy required to remove 1 mole of electrons from 1 mole of gaseous atoms, to form 1 mole of gaseous singly charged cations. M(g)  M+(g) + e−

9. The second ionisation energy of an element (H2nd I.E.), is the energy required to remove 1 mole of electrons from 1 mole of gaseous singly charged cations, to form 1e mol of gaseous doubly charged cations. M+(g)  M2+(g) + e−

10. The first electron affinity of an element (H1st E.A), is the enthalpy change when 1 mol of electrons are added to 1 mol of gaseous atoms, to form 1 mol of gaseous singly charged anions.

11. Lattice energy is the energy evolved when 1 mole of an ionic solid is formed from its constituent gaseous ions under standard conditions 25C and 1 atm.

12. The standard enthalpy change of hydration of a gaseous ion (Hhyd), is the enthalpy change when 1 mole of hydrated aqueous ions is formed from the gaseous ions under standard conditions 25C and 1 atm. .

13. The standard enthalpy change of solution of an ionic compound (Hsoln), is the enthalpy change when 1 mole of an ionic compound is dissolved in a large excess of water under standard conditions 25C and 1 atm.

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A-Level Mathematics Tuition Singapore/JC Maths/H2 Math Tuition and Tutor

Hi A-Level/H2 Math Students

J1 – Teaching Vectors 1

J2 – Teaching Hypothesis Testing & Practice Exam Papers

From A Level Math Tutors

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A-Level Physics Tuition Singapore/H2 Physics Tuition/JC Physics Tutor

Hi A-level/H2/JC Physics Tuition students

Definitions – Gravitational Potential Energy

1. Newton‟s Law of Universal Gravitation
The gravitational force of attraction between two point masses is directly proportional to the product of their masses and inversely proportional to the square of their distance apart.

2. Gravitational Field
A gravitational field is a region of space in which any mass placed inside it will experience a gravitational force.

3. Gravitational Field Strength
The gravitational field strength, g, at a point in a gravitational field is defined as the gravitational force per unit mass acting on a small mass placed at that point. [It is also equal to the negative of the gravitational potential gradient at that point.]

4. Gravitational Potential Energy
Gravitational potential energy U of a mass m at a point in a gravitational field is defined as the work done by an external agent in bringing a mass from infinity to that point.

5. Gravitational Potential
The gravitational potential at a point in a gravitational field is defined as the work done by an external agent per unit mass in moving a point mass from infinity to that point.

6. Geostationary Orbit
A geostationary orbit is one whereby the satellite appears stationary relative to a fixed point on the surface of the Earth.
Three mandatory conditions:
1. Orbital period = 24 hours
(in general, the period of rotation of the planet it is orbiting)
2. Satellite must orbit same direction as Earth‟s (West to East)
3. Must be directly above the equator

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O-Level Additional Mathematics Tuition Singapore

S3 – Teaching mid-point of a line segment and parallel lines

S4 – Teaching application of Integration – Area of a region

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