In chapter 2, there are 7 base units in an SI. A base unit is a defined unit in a system of measurement that is based on an object or event in the physical world. EX: The SI Base Unit for time is seconds. It also talks about density, Density is the property that can be used to identify an unknown sample of matter. The Chapter also talks about matter matter is considered anything that has a mass and volume. There is also the kelvin scale a kelvin scale is a thermodynamic temperature scale based on the efficiencies of ideal heat engine a heat engine typically uses energy provided in the form of heat to do work and then exhausts the heat which cannot be used to do work. It has numbers that are put together and it shows how they work together. There is also scientific notation, Scientific Notation is when measurements are multiplied or divided, their exponents are either added or subtracted. Chemical reactions can help in chapter 2 because you can mix different substances to see the different reactions a chemical reaction is a process that leads to the transformation of one set of chemical substances to another. some of the reactions can have energy changes, energy changes come in a number of different forms and that we can make a list of 10 types of energy to help identify and talk about energy. That is some of the things in chapter 2.

The TEKS for UNITS of MEASUREMENT is 2 (F) which says Collect data and make measurements with accuracy and precision. The Accuracy of a measurement system is the degree of closeness of measurements of a quantity to that quantity's actual (true) value. The Precision of a measurement is the degree to which repeated measurements under unchanged conditions show the same results.

The TEKS for Scientific Notation and Dimensional Analysis is 2(G)- it says express and manipulate chemical quantities using scientific conventions and mathematical procedures, including Dimensional Analysis, Scientific Notation, and Significant Figures.

The TEKS for How reliable are Measurements? is also 2(F)- which says collect data and make measurements with accuracy and precision.

The TEKS for Representing Data is 2(H) and 2(I): 2(H) says to organize, analyze, evaluate, make inferences, and predict trends from data, and 2(I) says communicate valid conclusions supported by the data through methods such as lab reports, labeled drawings, graphs, journals, summaries, oral reports, and technology-based reports.

In chapter 3, there are different forms of substances. A substance is a form of matter with a uniform and unchanging composition. there is also matter. matter is anything made of atoms and molecules, the 3 common states of matter are solid, liquid, and gas. it also talks about chemical changes and chemical reactions chemical changes are substances that are changed into different substances. a chemical reaction is a process that leads to the transformation of one set of chemical substances to another. it also shows different cycles. when it explains substances it shows the mixtures of substances, how they are used together, and what they are used for. You can mix different substances to make chemical reactions and you can see what the reactions are and make, those chemical reactions can make energy changes. in chapter 3 you can see what those energy changes do and what they make.

3.1) Properties of Matter the TEKS are 4(A) and 4(C). 4(A) says differentiate between physical and chemical changes and properties and 4(C) says compare solids, liquids, and gases in terms of compressibility, structure, shape, and volume.

3.2) Changes in Matter the TEKS are 4(A) and 8(D) 4(A) says differentiate between physical and chemical changes and properties and 8(D) says to use the law of conservation of mass to write and balance chemical equations. The Law of Conservation of Mass which is also known as the principle of mass/matter conservation.states that the mass of an isolated system (closed to all matter and energy) will remain constant over time. This principle is equivalent to the conservation of energy, in the sense when energy or mass is enclosed in a system and none is allowed in or out, its quantity cannot otherwise change (hence, its quantity is "conserved").

3.3) Mixtures of Matter the TEKS are 4(D) which says to classify matter as pure substances or mixtures through investigation of their properties. Pure substances contain only one type of substance (they can be elements or compounds). For example, a jug of distilled water contains only water molecules (H2O) so that is a pure substance. Just like a piece of copper wire only contains copper atoms, that is a pure substance. A mixture is a substance made by mixing other substances together.

3.4) Elements and Compounds the TEKS are 5(A), 5(B) and 6(D). 5(A) says to explain the use of chemical and physical properties in the historical development of the Periodic Table.

5(B) says to use the Periodic Table to identify and explain the properties of chemical families, including alkali metals, alkaline earth metals, halogens, noble gases, and transition metals.