NeSA- INQUIRY, THE NATURE OF SCIENCE, AND TECHNOLOGY Abilities to do Scientific Inquiry

1. NeSA- INQUIRY, THE NATURE OF SCIENCE, AND TECHNOLOGYAbilities to do Scientific Inquiry SC 12.1.1 Students will design and conduct investigations that lead to the use of logic and evidence in the formulation of scientific explanations and models.

2. Objective •Formulate a testable hypothesis supported by prior knowledge to guide an investigation A scientific hypothesis is a prediction which can be tested through controlled experimentation. Scientists base their hypotheses on observations, questions, previous knowledge (knowledge of scientific literature) and interpretations (biases). Practice • Which of the following is/are commonly used to establish a hypothesis? • a. scientific literature b. observations • c. previous personal knowledge d. all of these • 2. A hypothesis must be both a prediction and be testable. • a. true b. false Standard-SC 12.1.1.a

3. Answers & Explanation • (d) all of the above • Scientists design hypotheses based on observations of events, previous knowledge they have, knowledge that is contained in scientific literature and interpretations they have regarding possible relationships they can predict. Hypothesis propose a logical outcomes of events that occur through manipulating variables. • 2. (a) true • In order for a hypothesis to be tested in a scientific experiment it must make a prediction based on changes in independent variables and must be a statement that can be tested through controlled experimentation. Key Terms Standard-SC 12.1.1.a

4. Objective •Design and conduct logical and sequential scientific investigations with repeated trials and apply findings to new investigations The scientific method is the process by which scientists conduct controlled experiments. This form of scientific inquiry tests single variables (independent variable) by measuring its affect on another variable (dependent variable) Practice • The variable that is altered by the scientist in a controlled experiment is identified as • a. independent b. dependent c. controlled • 2. A controlled variable is • a. changed in each trial b. allowed to change in trials • c. held constant in each trial Standard-SC 12.1.1.b

5. Answers & Explanation 1. (a) independent A scientists purposefully alters ONE variable in an experiment in order to test changes in another variable. 2. (c) held constant in each trial Controlled variables are conditions in an experiment that should not affect the dependent variable. These should be the same for all individual trials. Key Terms Standard-SC 12.1.1.b

6. Objective •SC 12.1.1.c Identify and manage variables and constraints Scientific investigations are designed to test one variables (independent variable) influence on another variable (dependent variable) while attempting to keep all other variables constant (controlled variables). Practice • A study comparing the weight gain in mice due to the amount of fat in their diet was conducted. What is the independent variable? • a. amount of fat b. weight gain c. mass of food • 2. In the same study above, what is the dependent variable? • a. amount of fat b. weight gain c. mass of food Standard-SC 12.1.1.c

7. Answers & Explanation • (a) amount of fat • The research was studying the amount of fat in the diet and how it affects the weight gain in mice. The amount of fat in the diet was determined by the scientist and the weight gain by the mice was an effect of fat changes. The amount of fat is the independent variable because it is the variable that was purposefully changed. • 2. (b) weight gain • The weight gain by the mice was analyzed by comparing it to the amount of fat in the diets of the mice. The weight gain is considered dependent on amount of fat. Standard-SC 12.1.1.c

8. Objective •Select and use lab equipment and technology appropriately and accurately In order to conduct sound scientific investigations scientists must use appropriate equipment, data collecting instruments/devices and analyze data using appropriate means. Much of the collecting and analysis of data is done with technology. Practice • In order to test the acidity of a solution, a scientist would need a • a. balance b. scale c. pH meter d. meter stick • 2. What measure would a beaker or flask be able to provide? • a. mass b. length c. density d. volume Standard-SC 12.1.1.d

9. Answers & Explanation • (c) a pH meter • pH meters measure the acidity of a solution based on the concentration of hydrogen ions (H+) that exist in solution. The greater the concentration of hydrogen ions, the higher the acidity and the lower on the pH scale it is. Acids have pH values which are less than 7 and bases have pH values greater than 7 • 2. (d) volume • Beakers and flasks measure the volume of liquids (or gases) in the container. Standard-SC 12.1.1.d

10. Objective •Use tools and technology to make detailed qualitative and quantitative observations During a scientific investigation scientists must be able to make observations and measures which are free of bias. Two types of observations are quantitative (numeric) and qualitative (a description). Practice • An observation that describes the color of an objective would be • a. qualitative b. quantitative c. neither • 2. A quantitative observation can be • a. a count b. a measure c. both a & b Standard-SC 12.1.1.e

11. Answers & Explanation • (a) qualitative • Qualitative observations describe the physical attributes of an object. Examples are color, shape, texture, odor and taste. • 2. (c) both a & b • Quantitative observations are numeric descriptions of an object. Two ways that numeric observations can be made are counting objects or measuring objects. Measures can include mass, volume, length, density, brightness, and area. Standard-SC 12.1.1.e

12. Objective •Represent and review collected data in a systematic, accurate, and objective manner Scientists normally collect data from experiments and organize it into tables where changes in the dependent variables are recorded in relation to changes in the independent variable. Practice • Which student has the second longest finger? • a. Luke b. Wendy c. Pham d. Marcie • 2. Which student has the smallest length to circumference ratio? • a. Luke b. Angelina c. Wendy d. Marcie Standard-SC 12.1.1.f

13. Answers & Explanation 1. (c) Pham Luke has the longest finger (8.1 cm) and Pham has the second longest (7.2 cm) 2. (d) Marcie Marcie has the lowest ratio of length to circumference. She is the only student who has a finger which is shorter than the circumference. This puts her ratio lower than 1. All other students have ratios greater than 1 because their lengths are greater than their circumferences. Standard-SC 12.1.1.f

14. Objective •Analyze and interpret data, synthesize ideas, formulate and evaluate models, and clarify concepts and explanations Upon completing a scientific experiment and collecting non-biased data, a scientist must analyze the data and represent the results in a way that shows the relationship between the dependent and independent variable. Graphs are usually used to represent these relationships. Practice • Which region of the brain has the most receptor binding sites? • a. 1 b. 2 c. 3 d. 4 • 2. If region 1 is the outer most region and 4 is the inner most region, where are most receptor • binding sites found? • a. outer b. inner c. they are the same Standard-SC 12.1.1.g

15. Answers & Explanation • (b) 2 • Brain region #2 has over 50 binding sites where the other three regions have less than 40 binding sites. • 2. (a) outer • The outer regions ( regions 1 & 2) have more receptors than the inner regions (regions 3 & 4) Key Terms Standard-SC 12.1.1.g

16. Objective •Use results to verify or refute a hypothesis A conclusion is a statement that uses the results from an experiment to explain whether a hypothesis can be accepted, refuted or needs modification. Practice • A conclusion has to be a statement which answers the validity of a • a. hypothesis b. result c. data d. observation • 2. The conclusion should describe the relationship between the dependent variable and the • a. controlled variable b. dependent variable • c. independent variable Standard-SC 12.1.1.h

17. Answers & Explanation • (a) hypothesis • The conclusion needs to explain whether the data & results supported or did not support the hypothesis. • 2. (c) independent • Remember the hypothesis is a prediction of how a dependent variable will change in relation to an independent variable. The conclusion should state if the prediction was valid or not valid, based on what the results showed. Standard-SC 12.1.1.h

18. Objective •Propose and/or evaluate possible revisions and alternate explanations A scientific discussion is the explanation following a conclusion which describes the research, identifies possible errors within the research, proposes possible changes in the procedure and compares the conclusion to existing knowledge. Practice • A student predicted their dog would lose mass through the winter and spring. Did the results support their hypothesis? How should they change their hypothesis? Standard-SC 12.1.1.i

19. Answers & Explanation • The student’s hypothesis did not match their results. They predicted the dog would lose mass when it really gained mass. The results shows that the masses for each month increases from January to February. • The student should reject the hypothesis and restate it saying that their dog increases mass through the winter and spring. Standard-SC 12.1.1.i

20. Objective •Share information, procedures, results, conclusions, and defend findings to a scientific community (peers, science fair audience, policy makers) Scientists share the outcomes of research by publishing their findings in journals which are designed to evaluate the work through peer editing. It is this sharing that allows science to continually correct our understanding of the world around us. Practice • Tabloids, twitter and facebook are great sources of scientific research. • a. true b. false • 2. Why does scientific research need to be reviewed by the scientific • community? Standard-SC 12.1.1.j

21. Answers & Explanation • (b) false • Scientists commonly seek to publish their work in highly respected and peer-reviewed sources, such as scientific journal like Science, Nature, Annual Review of Biochemistry & Cell. These are highly ranked science journals. • 2. The process of reviewing scientific research allows other scientists to evaluate each others work. This is important so that incorrect work is not published and that science continues to find better explanations. Standard-SC 12.1.1.j

22. Objective •Evaluate scientific investigations and offer revisions and new ideas as appropriate The body of knowledge known as Science is a continually growing set of facts, ideas and predictions which are evaluated by other scientists, policy makers and other community individuals. This knowledge is built on everyone’s ability to question results, conduct further research and compare different ideas. Practice • Explain why it is important that scientists attend conferences, discuss their work and collaborate with each other on research projects. Standard-SC 12.1.1.k

23. Answers & Explanation 1. Scientific conferences are places where scientists who share a common interest or research subject meet to discuss current research and newly found information. They provide an opportunity for scientists to clarify their own research and develop new research directions. The October 1927 Fifth Solvay International Conference on Electrons and Photons, where the world's most notable physicists met to discuss the newly formulated quantum theory. The leading figures were Albert Einstein and Niels Bohr. Seventeen of the twenty-nine attendees were or became Nobel Prize winners, including Marie Curie, who alone among them, had won Nobel Prizes in two separate scientific disciplines. Standard-SC 12.1.1.k

24. Objective •Use appropriate mathematics in all aspects of scientific inquiry Mathematics is the process by which data is analyzed. Scientists use mathematic principles to seek relationships between variables in an experiment. Most graphs represent a mathematic model, outlining these relationships. Practice • Which of the lines in the graph above has a greater slope? • a. red line b. black line Standard-SC 12.1.1.l

25. Answers & Explanation • (a) red line • Data represented on a graph can be expressed as a mathematic equation. The slope of a line shows the linear relationship between two variables. A more vertical line has a greater slope and a more horizontal line has a less slope. Standard-SC 12.1.1.l

26. NeSA- Physical ScienceMatter SC 12.2.1 Students will investigate and describe matter in terms of its structure, composition and conservation.

27. Objective •Recognize bonding occurs when outer electrons are transferred (ionic) or shared (covalent) -Ionic bonds are formed between metals and nonmetals when electrons are transferred. This forms an ionic compound, also called a salt. -Covalent bonds are formed between two nonmetals when they share electrons. This forms a covalent compound called a molecule Practice 1. Which element below would form an ionic bond with iron? a. sodium b. oxygen c. gold d. copper 2. Chlorine atoms have 7 valence electrons. How many covalent bonds do they commonly form? a. one b. two c. three d. eight Standard- SC 12.2.1.a

28. Answers & Explanation • (b) Iron reacts with oxygen • Ionic bonds occur between metals and nonmetals. Metals lose electrons to nonmetals • because nonmetals have high pulls on electrons and metals have low pulls on electrons. • Losing electrons is called oxidation and gaining electrons is called reduction. • Iron reacts with oxygen to form rust, ferric oxide, Fe2O3 2. (a) Chlorine normally forms 1 covalent bond with other nonmetals. Nonmetals share their electrons with other nonmetals in order to fill their valence shell with eight electrons. They share because two nonmetals both have high pulls on electrons and therefore overlap to share electrons. Key Terms Standard-SC 12.2.1.a

29. Objective •Describe the energy transfer associated with phase changes between solids, liquids, and gasses Solid particles have the lowest energy and highest attraction. Melting occurs when heat overcomes the attractions and separates solid particles. Boiling occurs when liquid particles gain more heat to escape from each other’s attractions. Practice 1. Which of the following processes are endothermic? a. melting b. freezing c. boiling d. both a & c 2. When ice melts in your hand, energy moves from a. your hand to the ice b. the ice to your hand e. no movement of energy Standard-SC 12.2.1.b

30. Answers & Explanation • (d) Both melting and boiling • Both melting and boiling require an input of heat, endothermic. Freezing occurs when liquid particles lose energy and form a solid. • (a) your hand to the ice • Thermal energy moves from areas of high concentration (hotter) to areas of low concentration (colder) until a thermal equilibrium is obtained (temperatures become the same). For the ice to melt it has to gain heat which your hand provides. Your hand feels cold because it has lost heat. Standard-SC 12.2.1.b

31. Objective • Describe the three normal states of matter (solid, liquid, gas) in terms of energy, particle arrangement, particle motion, and strength of bond between molecules Practice 1. Which state of matter has particles with the highest energy? a. solid b. liquid c. gas 2. Which state of matter has constant shape and volume? a. solid b. liquid c. gas Standard-SC 12.2.1.c

32. Answers & Explanation 1. (c) gas Energy is either input into a substance or released from a substance. If energy is put in, the particles move faster and overcome their attractions. The movement of particles is a measure of energy. The more energy they gain, the faster they move. Solids become liquids and liquids become gases as the particles gain energy. When particles lose energy, they slow down and the attractions become greater. Gases become liquids and liquids become solids as their energy is released. 2. (a) solid Solid particles have the lowest energy and the highest attraction. The particles in a solid are therefore held into place (constant shape) through strong attractions and not free to move (constant volume). Standard-SC 12.2.1.c

33. Objective • Recognize a large number of chemical reactions involve the transfer of either electrons (oxidation/reduction) or hydrogen ions (acid/base) between reacting ions, molecules, or atoms Acid/base reactions occur when an acid donates a hydrogen ion (accepting electrons) and a base accepts a hydrogen ion (donating electrons). Redox reactions occur when one particle loses an electron and another gains an electron. Practice • Iron oxidizes in the presence of oxygen to form rust (iron oxide). What charge does the iron become if it is oxidized? • a. negative b. positive c. neutral • 2. Which of the following is true about bases? • a. they donate hydrogen ions b. they accept electrons • c. they accept hydrogen ions d. none of the above Standard-SC 12.2.1.d

34. Answers & Explanation • (b) positive • Oxidation occurs when an atom loses electrons. Losing electrons causes an atom to have more protons than electrons, which makes the atom more positive. • Reduction occurs when an atom gains electrons. Gaining electrons causes an atom to have more electrons than protons, which makes the atom more negative. Think of reduction as reducing charge by gaining electrons. • 2. (c) accept hydrogen ions • Acids are hydrogen ion donors and bases are hydrogen ion acceptors. You may also hear acids as proton donors and bases are proton acceptors because a hydrogen ion and a proton are basically the same thing. In order to lose a hydrogen ion to a base, the base must have a pair of electrons which the hydrogen can bond to (formation of a new covalent bond). Key Terms Standard-SC 12.2.1.d

35. Objective • Identify factors affecting rates of chemical reactions (temperature, particle size, surface area) A chemical reaction requires reactant particles to interact. Any factor that increases the interactions will increase the reaction rate. Here are four common factors : • Temperature- particles move faster and interact more • Surface area- the smaller the “pieces” are, the more they will interact. • Concentration- more particles in a space means more interactions • Catalysts increase interactions without changing themselves Practice • The rate of a reaction is measured by how fast reactants become products. • a. true b. false • 2. Which of the following will NOT increase the rate of a chemical reaction? • a. increasing temperature b. having gas particles instead of solid particles • c. decreasing concentration d. adding a catalyst Standard-SC 12.2.1.e

36. Answers & Explanation • (a) true • The rate of a chemical reaction is measured by how fast reactants are converted to products. • 2. (c) decreasing concentration • The rate of a reaction is affected by how fast reactants particles interact with each other. If the concentration of reactants is decreased (more spread out) the less they interact and the reaction rate decreases. Key Terms Standard-SC 12.2.1.e

37. Objective • Recognize the charges and relative locations of subatomic particles (neutrons, protons, electrons) Practice • Which of the following subatomic particles is found in the nucleus and has a positive charge? • a. neutron b. proton c. electron d. quark • 2. Which of the subatomic particles has the smallest mass? • a. neutron b. proton c. electron Standard-SC 12.2.1.f

38. Answers & Explanation • (b) proton • The proton has a positive charge and is located in the nucleus. Neutrons have no charge and are located in the nucleus. Electrons have a negative charge and are located in the energy levels outside the nucleus • (c) electron • The electron has the smallest mass of the particles, approximately 1/2000th the size of a proton or neutron. The neutron and proton both have approximately the same mass. Key Terms Standard-SC 12.2.1.f

39. Objective • Describe properties of atoms, ions, and isotopes Atoms are the smallest particles of matter which have the properties of that matter. They are electrically neutral (equal protons and electrons). Ions are atoms which have gained electrons (anions) or lost electrons (cations). Isotopes are atoms of an element that have the same number of protons but different numbers of neutrons. Practice • An oxygen atom has an atomic number of 8 (contains 8 protons). How many electrons does an oxygen atom contain? • a. 4 b. 6 c. 8 d. 10 • The atomic number for lithium is 3 (3 protons). How many neutrons does the Lithium-7 • isotope (7Li) contain? • a. 3 b. 4 c. 5 d. 0 Standard-SC 12.2.1.g

40. Answers & Explanation • (c) 8 • The atomic number of an element is the number of protons found in the nucleus. Every atom, ions or isotope of a specific element contains the same number of protons. Atoms are electrically neutral and therefore contain the same number of protons and electrons. Oxygen atoms all contain 8 protons and 8 electrons. • 2. (b) 4 • Isotopes are atoms of an element that have different numbers of neutrons. The mass number of an isotope is equal to the number of protons + neutrons and is used to identify the specific isotope. This number is written after the name or as the upper left superscript with the symbol. Lithium-7 (7Li) would be an isotope of lithium which has 3 protons and 4 neutrons (3 + 4 = 7). Key Terms Standard-SC 12.2.1.g

41. Objective • Describe the organization of the periodic table of elements with respect to patterns of physical and chemical properties The periodic table to the right shows two sets of trends, the red arrows show increasing trends to upper right and the blue arrows shows the increasing trends to lower left. Practice • Which of the following elements has the largest atomic radius? • a. neon (noble gas) b. chlorine (halogen) c. potassium (alkali metal) • 2. Which family of elements have the highest pull on their electrons? • a. alkali metals b. transition metals c. noble gases Standard-SC 12.2.1.h

42. Answers & Explanation • (c) potassium (alkali metal) • The trend for atomic radius is to increase towards the bottom left of the periodic tables. Metals have larger radii than metals in the same period due to having lower pulls on their electrons. Nonmetals have a higher pull on their electrons and therefore are smaller than metals in the same period. • 2. (c) noble gases • The trend for pull on electrons is to increase to the upper right. Nonmetals have high pulls on their electrons, are smaller atoms than metals and tend to gain electrons. Metals have lower pulls on their electrons, are larger than metals and tend to lose electrons. Key Terms Standard-SC 12.2.1.h

43. NeSA- Physical ScienceForce and Motion SC 12.2.2 Students will investigate and describe the nature of field forces and their interactions with matter.

44. Objective • Describe motion with respect to displacement and acceleration Displacement is the distance travelled from the starting point with direction. Velocity is the rate at which an object changes its displacement. Acceleration is the rate at which an object changes its velocity. Practice • 1. What is the displacement of a car moving with a uniform velocity of • 20 meters per second west for 40 seconds? • a. 200 meters b. 200 meters west • c. 800 meters d. 800 meters west • What is the acceleration of the object represented by the following graph if it is travelling north? • 2 m/s2 north b. 4 m/s2 north • c. 8 m/s2 north d. 12 m/s2 north Standard-SC 12.2.2.a

45. Answers & Explanation • (d) 800 meters west • Displacement is a vector quantity that must include direction. • 20 m/s * 40 s = 800 meters west • 2. (b) 4 m/s2 north • The slope of a velocity/time graph is the acceleration of the object. Key Terms Standard-SC 12.2.2.a

46. Objective • Describe how the law of inertia (Newton's 1st law) is evident in a real-world event Newton’s 1st law is the law of inertia. It states that an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. Practice • What force causes a projectile to follow a curved path? • a. gravity b. friction • c. air resistance d. none of the above • Why does a chair stay at rest on the floor? • a. No forces are acting upon it. b. The forces acting on the chair are unbalanced. • c. The net force on the chair is zero d. None of the above Standard-SC 12.2.2.b

47. Answers & Explanation • (a) gravity • Projectiles accelerate toward the center of the earth due to the force of gravity. Therefore they follow a curved path. • 2. (c) The net force on the chair is zero. • If an unbalanced force acts on the chair its velocity will change. Key Terms Standard-SC 12.2.2.b

48. Objective • Make predictions based on relationships among net force, mass, and acceleration (Newton's 2nd law) Newton’s second law states that the acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object. This is often represented by the equation Force = Mass * Acceleration. Practice 1. For any object, the greater the force that's applied to it, the greater its ____ will be. a. inertia b. acceleration c. gravity d. velocity 2. A 3,000-N force acts on a 200-kg object. The acceleration of the object is ____. a. 50 m/s2 b. 150 m/s2 c. 15 m/s2 d. 26 m/s2 Standard-SC 12.2.2.c

49. Answers & Explanation 1. (b) acceleration A net force on an object will cause it to accelerate. 2. (b) 150 m/s2 By using the equation F=ma we can find that 3000 N / 200 kg = 150 m/s2. Key Terms Standard-SC 12.2.2.c

50. Objective • Recognize that all forces occur in equal and opposite pairs (Newton's 3rd law) Newton's third law states that for every action, there is an equal and opposite reaction. Therefore, all forces occur in pairs that are equal in magnitude and opposite in direction. Practice • 1. When a force is exerted on a box, an equal and opposite force is exerted by the box. These forces are called ____ forces. • a. frictional b. gravitational c. action-reaction d. centripetal • If the earth exerts a gravitational force of 980 N on you, what force do you exert on the earth? • a. 980 N in the same direction b. 980 N in the opposite direction • c. 0 N d. not enough information provided Standard-SC 12.2.2.d