The document discusses several key chemistry concepts including: 1) Density is a property of matter defined as mass per unit volume and determines if something will float or sink in a fluid. 2) Viscosity is a measure of a fluid's resistance to flow, such as honey being more viscous than water. 3) Buoyancy causes objects to float and is determined by an object's density compared to the fluid it is in.

2. Properties of Matter Density FACT: If it floats, it is less dense.

3. Properties of Matter Buoyancy Viscosity

5. density is an intensive property of matter - it does NOT change when you change the amount or shape of the sample.

7. 4.05 g / 12.0 mL = 3.775 g/mL density = mass/volume - given on the formula page of the TAKS. Mass will be given in grams. Volume will be in milliliters (mL) or liters (L). Check the units in the answers to ensure they match the mass and volume units given in the question.

9. Viscosity is resistance to flow. Think of thickness - honey vs. water. Honey is much more viscous than water. A - refers to density, which is unrelated to viscosity B - there is no information indicating the block will change the temperature of the solutions. C - displacement involves density and is unrelated to viscosity D - the time the block takes to move through the solution under the force of gravity (sinking) is dependent on viscosity, assuming the metal block is more dense than both solutions.

11. Buoyancy means floating. Buoyant force is how much a fluid pushes up on things floating in the fluid. Density determines buoyancy, so... Density goes with buoyancy! If a question asks about buoyancy, think about density. Think about the density formula.

12. Periodic Table

13. # of protons identifies the element. Count them and find the matching atomic #.

14. neutrons o Lithium (3 protons) protons + electrons – # of protons identifies the element. Count them and find the atomic #.

15. Columns on the PT are known as groups. Elements in the same GROUP have similar physical and chemical properties.

17. Metals tend to react with non-metals Tip: When asked about groups and how they react, label each answer choice as a metal or non-metal. The answer will become obvious.

19. Number of protons determines the identity of an element. Number of protons is the atomic number.

21. Elements with similar properties are in the same GROUP (column). Number of protons determines the identity of an element. Number of protons is the atomic number.

23. K is a metal (group 1) metals metals metals/metalloid nonmetals Metals react with nonmetals. Label the element in the prompt as metal or nonmetal, and then all the answers as metal or nonmetal.

26. nonmetal - group 17 nonmetal - group 15 metalloid - group 15 metal - group 13 ·Metals lose / donate / give electrons - group 1 loses electrons most readily ·Nonmetals gain / accept / take electrons - group 17 gains electrons most easily

28. When you see a question referring to the periodic table, refer to the one in your test! It is there to help you. ·Group 16 are nonmetals. ·Nonmetals gain / accept / take electrons - group 17 gains electrons most easily

32. a.k.a. Law of Conservation of Mass

34. reactants mass must equal products mass products reactants + = +

39. 1) Make a table under each compound. 2) Count number of atoms of each element in each compound. 3) Make the number of atoms of each element equal on each side of the equation by using whole number coefficients where needed. 2 PbO2 Coefficient You can change this. Subscript You CANNOT change this. In "3 SO2" there are 3 Sulfur and 6 Oxygen atoms.

45. Ask yourself, is it still the same thing it was before the change took place? If not, it's usually a chemical change. still ice, just broken, physical still sugar, just dissolved, physical This milk is not milk anymore. It's gross. still lead, just in liquid form, physical

47. acids = chemical changes "combining...to form hematite" = new substance = chemical acids = chemical changes broken shale is still shale. say this 5 times fast

50. Water is polar and uses its polarity to dissolve any substance that is also polar.

53. think: HEAT CRUSH STIR! HEAT, not cool NOOOOOO! not a factor for solubility of a solid

56. pH of the mixed solution is more basic not a factor in pH not a factor in pH not a factor in pH YES Only changing the concentration of H+ ions and OH- ions can change the pH of a solution.