CHEM1305 Pearson Mastering Chemistry Chapter Reading PDF

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Mastering Chemistry Pearson Homework Chapter Reading: Chapters 1-2
Professor: Kwiatkowski
Term: Fall 2021
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SFASU CHEM1305.300 Introductory Chemistry I [Kwiatkowski] Pearson MyLab and Mastering Chemistry Chapter 1.1 Sand and Water Richard Feynman (1918-1988) – Nobel laureate said, “the most important idea in all human knowledge is that all things are made of atoms.” Important because – it establishes how we should go about understanding the properties of the things around us. If we want to understand how matter behaves, we must understand how the particles that compose that matter behave.

Chemistry – the sceince that tries to understand how matter behaves by studying how atoms and molecules behave. Chapter 1.2 – Chemicals Compose Ordinary Things -

Recognize that chemicals make up virtually everything we come into contact within our world. Chapter 1.3 – The Scientific Method: How Chemists Think

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Identify and understand the key characteristics of the scientific method o Observation – measurement of some aspect of nature. Some are simple, requiring nothing more than the naked eye and other rely on the use of sensitive instrumentation or entirely by chance. Alexander Fleming (1881-1955) discovered penicillin when he observed a bacteria-free circle around a certain mold that had accidentally grown on a culture plate. Antoine Lavoisier (17431794), a French chemist who studied combustion, burned substances in closed containers and measured mass of each container and its contents before and after burning the substance inside, noting that there was no change in the mass during combustion = made an observation about the physical world. Observations often lead to a hypothesis. o Formulation of hypotheses – a theory or law before it has become well established; a tentative explanation for an observation or a scientific problem that can be tested by further investigation. A good hypothesis is falsifiable, which means that further testing has the potential to prove it wrong. o Testing of hypotheses by experiment – highly controlled observations designed to validate or invalidate hypotheses. An experiment is defined as a procedure to measure observable predications to test a theory or law. o Formulation of laws and theories. – a statement that summarizes past observations and predicts future ones. Scientific laws are usually formulated from a series of related observations. Lavoisier developed law of conservation of mass – a law stating that in a chemical reaction, matter is neither created nor destroyed.  scientific theory which is a proposed explanation for observations and laws. A theory presents a model of the way nature works and predicts behavior that extends well beyond the observations and laws from which it was formed. Also called models. Scientific Method – a way of learning that emphasizes observation and experimentation – to understand the world.

Everyday Chemistry Louis-Bernard Guyton de Morveau (1737-1816) – mid-18th century scientist weighed metals before and after burning them. The metals gained weight when they were burned. Was inconsistent with the phlogiston theory – predicts that metals should lose weight because phlogiston was supposed to be lost during combustion = theory needed modification. Theory was proven wrong. What is the difference between a law and a theory – a law predicts what happens while a theory proposes why. A theory will never grow up into a law, though the development of one often triggers progress on the other. Chapter 1.4 – Analyzing and Interpreting Data -

Identify patterns in data and interpret graphs – seeing patterns is a way to see relationships that may not always be obvious. o Interpreting Graphs – graphs or images (can demonstrate rates of increase or decrease in an experiment).

Chapter 1.5 – A Beginning Chemist: How to Succeed To succeed as a chemist: 1. You must have the curiosity and imagination of a child – you must want to know the why of things. 2. Chemistry requires calculation. 3. Chemistry requires commitment. Pure Substance - A pure substance consists of only one type of atom or molecule. Sugar (glucose), carbon dioxide, and water are examples of pure substances. Gasoline is a mixture of multiple pure hydrocarbons. Brass and bronze are metal alloys made up of several different types of metal atoms. Chapter 2 – Measurement and Problem Solving Chapter 2.1 – The Metric Mix-Up: A $125 million Unit Error Unit – a standard, agreed on quantity by which other quantities are measured. Chapter 2.2 – Scientific Notation: Writing Large and Small Numbers Express very large and very small numbers using scientific notation. Scientific Notation – A system used to write very big or very small numbers, often containing many zeros, more compactly and precisely. A number written in scientific notation consists of a decimal part and an exponential part (10 raised to a particular exponent). Decimal Part – one part of a number expressed in scientific notation.

Exponential Part – One part of a number expressed in scientific notation; it represents the number of places the decimal point has moved. Exponential Part – One part of a number expressed in scientific notation; it represents the number of places the decimal point has moved. Exponent – a number that represents a number times a term is multiplied by itself. For example, in 2^4 the exponent is 4 and represents 2x2x2x2. A positive exponent (n) means 1 multiplied by 10n times. A negative exponent (-n) means 1 divided by 1 n times.

Large numbers have positive exponents and small numbers have negative exponents. Chapter 2.3 – Significant Figures: Writing Numbers to Reflect Precision Report measured quantities to the right number of digits. Determine which digits in a number are significant. When a number is expressed in scientific notation, all trailing zeros are significant. Exact Numbers – have an unlimited number of significant figures. They originate from 3 sources. 100 cm = 1 m means 100.00000…cm = 1.00000…m Radius = diameter/2 2 is exact and therefore has an unlimited number of significant figures. 0.0035 has 2 significant figures. 1.080 has 4 significant figures. 2371 has 4 significant figures. 2.97 x 10^5 has 3 significant figures. 1 dozen = 12 unlimited significant figures. 100.00 has 5 significant figures. 100,000 is ambiguous.

Chapter 2.4 Significant Figures in Calculations...