SCIENCE REVIEWER
1. In the main sequence star, what element is formed when hydrogen fuse in the star’s core?
- Helium
2. At approximately what temperature can nuclear reaction in a star’s core occur?
- 10,000,000 Kelvin
3. Through what process are stars in the universe formed?
-Nuclear fusion
4. How is the heavy element Carbon formed in a star’s core?
-Helium fusion
5. Where is the site of the formation of heavier elements in the universe?
-Star
6. How many Helium atom/s fuse/s together to produce Carbon?
-3
7. What piece of evidence of star formation provides a view of stars due to their heat energies?
-Infrared radiation
8. What heavier element can a supergiant star only produce up to?
-Iron
9. Which of the following is the correct sequence of the evolution of the star?
-main sequence star,red giant, supergiant, supernova
10. What stage of the evolution of the star produces the element Iron (Fe)?
-Supergiant
11. What fuel is needed in a red giant star to begin its fusion reaction?
-Helium
12. What signals the doom or death of a star?
-Supernova
13. How are elements heavier than Iron (Fe) formed?
-Fusion of more alpha particles
14. What happens to the mass of a star as time goes on?
-Heavier
15. What happens to the core temperature of a star as it ages/ evolves?
-Increases
16. Who among the scientists paved the way in discovering new elements using the concept of X-rays?
-Henry Moseley
17. What is the first man-made element discovered in 1937?
-Technetium
18. What determines in identifying of a new synthesized element?
-Atomic number
19. What device is used by scientists to synthesize the elements Technetium and Astatine with atomic numbers 43 and 85, respectively?
-Particle accelerator
20. What atomic number marks the start of transuranium elements of the Periodic Table of Elements?
-92
21. Hydrogen has an atomic number of 1. What does atomic number mean in an element?
-Number of protons
22. Which of the following transuranium elements is used to coat steel to prevent corrosion?
-Technetium
23. Which statement below best describes the structure of a polar molecule?
-One end is positively charged and the other is negatively charged.
24. Which of the following molecules is polar?
-CI3
25. Which among the following factors does not contribute to the overall polarity of the molecule?
-Difference in atomic masses of each element in the molecule
26. Which among the substances below represents a polar molecule?
-NH3
27. What is the molecular geometry shape, and overall polarity of an SO3 molecule?
-Trigonal Planar, Nonpolar
28. Which statement best explains why carbon tetrachloride (CCl4) is a nonpolar molecule?
-The carbon tetrachloride molecule is symmetrical.
29. Which of the following statements best explains why oil-based paints are best cleaned by using paint thinner?
-Oil is non-polar which can be dissolved by non-polar substances like thinner
30. Which of the following properties describe a non-polar molecule?
-Gaseous in room temperature
31. Each of the following properties is related to the polarity of the molecule EXCEPT?
-Difference in atomic masses of each element in the molecule.
32. Anna is trying to dissolve a non-polar substance in her experiment, which of the following solvents should she use?
-A non-polar solvent
33. Which of the following are the reasons why strong acids conduct electricity when dissolved in water?
-They disassociate into ions allowing electricity to flow
34. Which statement best support carbon tetrachloride (CCl4) is non-polar?
-Carbon tetrachloride is insoluble in water
35. Which of the following statements best explains why non-polar molecules easily evaporate and have low melting points compared to polar molecules?
-Non-polar molecules have weak intermolecular forces
36. When you mix-up a salad dressing with some vinegar and olive oil you can observe that over time the oil separates from the vinegar, what could be the cause of this phenomenon?
-Vinegar and oil have different polarities
37. In a lab setup, three beakers are filled with unknown liquids. The
following observations have been made.
ii. Liquid C does not mix with A and B
Which among these is most likely a non-polar liquid?
-Liquid C
38. What inference can we make from the observations?
-Liquids A and B are polar
39. Which statement best explains why Liquid C is most likely a non-polar liquid?
-It easily evaporates
40. If all three liquids were to be dissolved in gasoline, which of the following would most likely be the result?
-Liquid C would fully dissolve
41. In normal room temperature, which statement is true about non-polar substances?
-Most non-polar substances are gases.
42. Three beakers are filled with three unknown liquids, one of them is a polar substance. How would you identify which substance is polar?
-Mix the samples with water, the polar substance should dissolve fully
43. Which of the following substances is most likely a polar molecule?
-Substance C, a paint thinner for water-based paints
44. What type of Intermolecular force of attraction exists between molecules that are non-polar?
-London Dispersion
45. What type of Intermolecular Force of attraction exists between molecules with hydrogen bonded to high electronegative atom such as Oxygen, Nitrogen, and Fluorine?
-Hydrogen Bonding
46. Which of the following examples below is exhibits dipole-dipole intermolecular force of attraction?
-The partial positive pole of iodine monochloride is attracted to the partial negative pole of another iodine monochloride molecule.
47. Which of the following exhibits a Hydrogen Bonding as a type of Intermolecular force of attraction?
-Two molecules of ammonia (NH3) attracted to one another with opposing charges in its pole.
48. Which of the following exhibits a London Dispersion intermolecular force of attraction?
-Two Diatomic hydrogen gas attracted to one another with an instantaneous force of attraction.
49. Which of the following statements below is true with regards to London-dispersion force of attraction?
-It is short-lived as a result of instantaneous dipole of non-polar molecules.
50. Which of the following exhibits an ion-dipole intermolecular force of attraction?
-A molecule of water attracted to a cation with their opposing charges.
51. Which of the following is true with regards to dipole-dipole intermolecular force of attraction?
-It is a result of attraction between two polar molecules with their opposing partial charges.
52. Which of the following is true with regards to Ion-dipole force of attraction?
-It is the attraction between molecules containing a polar molecule bonded to an ion.
53. Which of the following statements below is true with regards to hydrogen bonding as a force of attraction?
-It is a special type of dipole-dipole interaction between molecules containing hydrogen bonded to a highly electronegative atom.
54. Which of the following molecules below exhibits a London-dispersion force of attraction?
-The interacting molecules of Water containing sodium ion.
55. Which of the following intermolecular forces of attraction below is considered as the strongest?
-Ion-Dipole
56. Which of the following intermolecular forces of attraction below is considered as the weakest?
-London Dispersion
57. Which of the following statements below is TRUE with regards to London Dispersion as Intermolecular Force of Attraction?
-It is the weakest type Intermolecular Force.
58. Which of the following statements below is TRUE with regards to Hydrogen Bonding as Intermolecular Force of Attraction?
-Contains hydrogen bonded to an electronegative element
59. Which of the following show/s how intermolecular forces affect properties of different substances?
-Both A and B
60. How does intermolecular forces affect the melting/boiling point of a substance?
-It takes longer for a substance to reach its melting and boiling point when the intermolecular forces are strong.
61. What happens to the vapor pressure as you increase the strength of intermolecular forces of attraction? The vapor pressure _________________.
-decreases
62. Which of the following IS NOT influenced by the type of intermolecular forces?
-Weight
63. Geckskin TM is a new super-adhesive based on the mechanics of gecko feet. It is so powerful that can easily attach and detach everyday objects yet can be easily released without leaving any residue. What effect of intermolecular forces explains the mechanism of this product?
-Surface tension
64. Which of the following is not a phase transition?
-Melting
65. Like dissolve like refers to which properties of substance?
-Vapor pressure
66. What happens to the boiling point as you increase the strength of intermolecular forces of attraction? The boiling point _________________.
-Increases
67. The more structurally complex the molecules in a liquid the stronger the intermolecular forces present. Which of the following explains the effect of IMFA on properties of substance?
-Viscosity
68. What property of a substance explains the effect of IMFA on the temperature at which the vapor pressure becomes equal to the pressure exerted on the surface of the liquid?
-Melting point
69. Which phase of matter has the strongest intermolecular force of attraction?
-Steam
70. Which of the following describes the tendency of a liquid to attain the smallest possible surface area?
-Solubility
71. Which of the following refers to the measure of a fluid’s resistance to flow?
-Viscosity
72. Which of the following describes the amount of pressure (force per unit area) applied by a gas above any liquid in a sealed container?
-Vapor pressure
73. Which of the following is a measure of the mass in a unit volume?
-Boiling point
74. A carbohydrate is a biomolecule consisting of carbon, hydrogen and oxygen atoms, usually with a hydrogen–oxygen atom ratio of 2:1 and typically can be broken down to release energy in the animal body. Which of the following is NOT a carbohydrate?
-Glycine
75. Amino acids have both an amino group and a carboxyl group in their structure. Which one of the following is an amino acid?
-Glycine
76. Biomolecules are organic molecule that includes carbohydrates, protein, lipids, and nucleic acids. They are important for the survival of living cells. Which of the following is a byproduct of a chemical union of the basic units of carbohydrates, lipids, or proteins?
-energy
77. Adjacent nucleotides in a nucleic acid are joined by a phosphodiesterase bond. This bond links the phosphate group of one nucleotide to which one of the following components of a neighboring nucleotide?
-Phosphate group
78. Lipids organic compounds that are fatty acids or their derivatives are insoluble in water but soluble in organic solvents. Which of the following explains why sterols (or steroids) are considered to be lipids?
-They are used as storage fats.
79. A macromolecule is a very large molecule, commonly composed of the polymerization of smaller subunits called monomers. Which of the following would most likely qualify as a macromolecule?
-DNA
80. Glucose and fructose both have the formula C6H12O6, but the atoms in these two compounds are arranged differently. Which of the following are glucose and fructose known for?
-polysaccharides
81. Lipids are energy-rich organic, non-polar molecules. These organic compounds contain carbon, hydrogen and oxygen atoms that form a framework for the structure and function of living cells. They are insoluble in water and only soluble in nonpolar solvents as water is a polar molecule. Which of the following IS NOT a lipid?
-Proteins
82. When a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g. sucrose being broken down into glucose and fructose), this is recognized as saccharification. When disaccharides are changed to monosaccharides, the common chemical process involved is ______________.
-synthesis.
83. Nucleic acids are large biomolecules, essential to and life and are composed of nucleotides, a 5-carbon sugar, a phosphate group and a nitrogenous base. Which of the following is a major function of nucleic acids?
-storage and transfer of genetic information
84. Cholesterol is an example of lipids. Which of the following best describes cholesterol as essential for normal membrane functions?
-It keeps membranes fluid.
85. Proteins perform many physiological functions like enzymes. Which of the following represents an additional function of some protein discharge?
-Pigment conferring color to skin
86. Proteins are large biomolecules, or macromolecules, consisting of one or more long chains of amino acid residues. Which of the following do tremendously complex molecules use as their basic units or building blocks?
-synthesis
87. Assume that DNA molecules are studied in a variety of organisms and found to have the following properties. Which property would be consistent with the hypothesis that genetic material is composed of DNA?
-DNA is different in two different cells of the same organism
88. When a protein is boiled, it loses all levels of organization besides the primary level. Which of the following will happen to protein?
-It will be denatured
89. What will happen to the kinetic energy of the particles enclosed in a container when the temperature of the container increases?
-decrease of kinetic
90. Which of the following is the result when there is a decrease in temperature of the reactants?
-allow less effective collision between the particles
91. Which of the following best describes activation energy?
-The energy added by a catalyst
92. Which factor increases the rate of reaction?
-same reaction rate
93. Why does a higher temperature increase the rate of reaction?
-It increases both the frequency and energy of particle collisions
94. Why does a higher concentration increase the rate of reaction?
-it increases the frequency of particle collisions
95. Which of the following is the result of more collisions?
-faster reaction rate
96 Why does a higher concentration increase the rate of reaction?
-collisions must occur between reactant particles
97. Which is the effect of faster product formation?
-the particle size of the reactants is larger
98. Which of the collisions is brought about by a chemical reaction?
-consistent collisions
99. Which will happen most likely happen when there are more collisions?
-faster reaction rate
100. Which of the following is/are the fundamental idea/s of collision theory?
-Molecules react by colliding together
101. What two factors govern whether a collision between reacting particles will be effective?
-kinetic energy and orientation
102. Why does a higher temperature increase the rate of a reaction?
-it only increases the energy of particle collisions
103. According to the collision theory, the particles must collide with ____ and ____ for a reaction to occur.
-sufficient energy; correct orientation