HESI CHEMISTRY V1/V2 (140 Questions and Answers)
1. If Hydrogen is in a compound, what would its oxidation number be?
2. What is the oxidat... [Show More] ion number of any simple ion?
The same as the charge of the ion
3. How many kilograms are in a pound?
4. What is the temperature for freezing point of water in Celsius?
0 degrees Celsius (32°F for Fahrenheit)
5. What is the conversion of Celsius to Fahrenheit?
5F=9C+160 (remember 5F because you have 5 fingers on a hand & 9C because cats have 9 lives)
6. What is the oxidation number of an element atom?
7. What is the freezing point of sea water in Fahrenheit?
Below 0C (pick and answer choice around -2C, actual temp depends on how much salt is in the water)
8. How many amino acids are in a dipeptide?
9. If Oxygen is in a compound, what would its oxidation number be?
10. Which of the following pH values would lemon juice likely have?
2 because the lower the pH value, the more acidic
11. What is a pentose?
A 5 carbon sugar (Pent = 5) (ose = sugar)
12. What is the oxidation state of the Sulfur atom in Sulfuric Acid H2SO4?
6 (each H is +1, each O is -2. All charges have to add to 0. 2+S-8=0, so S=6)
13. How many neutrons does carbon 14 have?
8 ( mass# - atomics # = neutrons) 14 - 6 = 8
14. How many protons does Potassium have?
19 (same as the atomic number)
15. How many amino acids are essential for human life?
20 amino acids
16. Normal body temperature in °C?
17. Normal body temperature in °F?
18. Boiling point of water in °C?
19. Boiling point of water in °F?
20. 0°K is equal to °C?
21. The term Amphoteric means?
A substance that can act as both a base & acid
22. What is Kelvin based around?
23. A compound that is a Hydrogen or proton donor, corrosive to metals, causes blue litmus paper to become red and becomes less acidic when mixed with a base is?
24. Mixture of 2 or more metals are?
• pH less than 7.0
• Formulas begin with H (Hydrogen)
• Proton Donor
26. 3 types of radiation in nuclear chemistry?
Alpha, Beta & Gamma
27. Alpha radiation:
• * Emission of Helium (He) ions in the nuclei
• * Contains 2 protons & 2 neutrons.
• * +2 Charge
• * Largest radiation particle.
• * Can be stopped by piece of paper
28. Type of Alloy in which another metal is dissolved in Mercury (Hg)?
29. Proteins are made up of?
30. Glycogen is what kind of starch?
31. When an atom GAINS ONE or more electrons?
Anions (negative ion)
32. Basic building block of a molecule?
33. Atomic mass?
Average mass of an elements isotope
34. Atomic #:
# of protons in nucleus of an atom
• A Hydrogen or proton ACCEPTOR & has hydroxide group in the makeup of the molecule
• Produce -OH
• Bitter, slippery, conduct electricity, formulas contain -OH
• pH value greater than 7.0
• Proton acceptor
36. Key note:
Acids are Proton donors and Bases are proton acceptors
37. Beta radiation:
• Decomposition product of a proton or neutron
• High speed/energy Electrons
• EITHER - charged electrons or + charged positrons
• Can be stopped by aluminum foil
38. What is Biochemistry?
Study of substances & processes occurring in living things
39. Fahrenheit is based off of?
40. How does ↑ Surface area speed up chemical reactions?
By ↑ areas of contact where chemical reactions can occur
41. How do catalyst accelerate a chemical reaction?
By reducing the amount of energy needed for a reaction to occur
A catalyst is a substance that accelerates a reaction by which of the following? -Finding an alternative pathway for a reaction that requires less energy.
42. What does COOH symbolize?
A Carboxyl group
43. Which of the following is not a solution type?
44. Define Catalyst.
Substance that speeds up a chemical reaction.
45. What is an atom called when it LOSES 1 or more electrons?
Cations (positive ions)
46. What is chemical bonding?
The joining of atoms to form new substances. 2 types: ionic & covalent bonding
47. What is an Ionic bond?
• Electrical attraction between 2 oppositely charged atoms called ions
• (between metals & nonmetals)
48. Ionic bonding?
Chemical bond that’s formed when an atom transfers an electron to another atom.
Single Covalent bond?
Chemical bond that shares 1 electron pair Formed by non-metals
Sharing is caring! Caring is covalent!
What are chemical reactions?
Making & breaking of chemical bonds, leading to changes in composition of matter
Double Covalent bond?
When 2 electron pairs are shared
Triple Covalent bond?
When 3 electron pairs are shared
The following is an example of?
Combustion reaction (in combustion, O2 is always a reactant, CO2 and H2O are always products the second reactant is the compound being combusted)
2C2H6 (g) + 7O2 (g) 4CO2(g) + 6H2O
54. What is a combustion reaction?
A chemical reaction that occurs when a substance reacts with Oxygen, releasing energy in the form of heat & light (also releases carbon dioxide & water)
55. What is a compound?
• Combination of 2 or more elements or atoms.
• Made up of atoms of 2 or more different elements joined by chemical bonds
56. Different types of solutions?
Compounds, Alloys, Amalgams, Emulsions
57. Strongest type of chemical bond?
58. What is a decomposition reaction?
A SINGLE compound breaks down to form 2 or more simpler substances
59. What is Deoxyribose?
A sugar used in the formation of DNA
60. Attractions between opposite charges of polar moles?
61. What is a Disaccharide?
A double sugar molecule made of 2 monosaccharides bonded together through
62. When 2 monosaccharides are joined together this makes?
63. Type of chemical bond that share 2 electron pairs?
Double covalent bond
64. Example of double replacement?
AB + CD = AD + CB (swapping dance partners)
65. Example of Single replacement?
A + BC B + AC (one dancer cutting in on two partners)
66. Group of electrons revolving around the nucleus of an atom, or known as a cloudlike
group of electrons? Electron clouds
67. Mixtures of matter that readily separate such as water and oil? Emulsion
68. 3 common temperature systems? Fahrenheit, Celsius, Kelvin
69. Celsius is based around? Freezing & boiling point of water
70. What is oxidation?
Loss of electrons (OIL: oxidation is losing)
71. What is reduction?
GAIN of electrons (RIG: reduction is gaining)
72. Gamma radiation:
• Similar to xrays
• Can be stopped by several feet of concrete or several inches of Lead
• High energy electromagnetic radiation lacking charge and mass
73. Unit measure of weight? Gram
74. Basic units of METRIC system? Gram, Liter, Meter
75. What are Hydrogen bonds?
Weak attraction between a hydrogen atom in one molecule & another atom in a different molecule.
76. Examples of intermolecular forces?
Hydrogen bonds, dipole-dipole, dispersion forces (attractions between two different molecules. Intramolecular bonds are ionic & covalent bonds within a single molecule)
77. 4 basic ways to speed up a reaction?
↑ temperature, ↑ Surface area, ↑ catalyst & ↑concentration
78. What are intermolecular forces?
Forces of attractions between molecules
79. Where are nucleic acids, DNA & RNA found? Cell nucleus
80. Atoms of the same element but have different numbers of neutrons? Isotope
81. Gluconeogenesis is a process that produces?
Glucose from proteins and fats rather than carbohydrates
82. A way to express concentration of atoms? Molarity
83. Part of the nucleus of an atom that has no charge? Neutron
84. What is the Molarity Formula?
Moles of Solute =Molarity Liters of Solution
85. Single sugar molecules? Monosaccharides
86. How does ↑ concentration cause reaction acceleration? More potential for contact (chemical reaction)
87. Which is an example of a ionic bond?
NaCl (Sodium Chloride) because it contains a metal and a non-metal (metal is always first)
88. In a covalent bond compound, if the electrons are shared equally, then the bond is?
Non-polar (water hating, equal)
89. The study of changes that occur in atomic nuclei? Nuclear Chemistry
90. Polar Covalent bond?
Unequal sharing of electrons (water loving)
91. When 3-6 monosaccharides join together this is called?
Oligosaccharide (7 or more: polysaccharide. Sometimes 3 or more is called a polysaccharide)
92. Emission of particles or energy from an unstable nucleus?
93. Particles that are emitted during radioactivity? Radiation
94. Reactant is?
A chemical substance that is present at the start of a chemical reaction. Reactant Product
95. A substance that is dissolved in a solution?
Solute (the liquid it is dissolved in is the solvent. In salt water, salt is the solute & water is the solvent)
96. A homogenous mixture of 2 or more substances? Solution
97. Liquid substance capable of dissolving other substances?
98. Define stoichiometry.
Calculation of quantities in chemical reactions
99. Combining parts into a whole is? Or synthesis is?
Chemical reaction in which 2 elements or simpler compounds combine to form a product
100. How many electrons does an Oxygen ion have?
10 (Atomic # of 8 & is in group VIA which has a -2 charge, which means it has 2 more electrons than the 8 protons)
101. What is the charge of Potassium (K) in KCl?
+1 because K is found in group IA
102. What is the mass of 1 mole of CO2?
44g/mol (C =12.011 + (15.999 x 2) = answer. You will be given the masses of the individual elements)
103. How many moles of atoms are present in 2 moles of O2? 4 (2 atoms in each molecule x 2 moles = 4 moles)
104. What characterizes a chemical reaction as combustion? The chemical reaction that is the reaction of a compound with Oxygen?
• O2 is a reactant, CO2 and H2O are products
105. Sum of oxidation # =? Charge on polyatomic ion
106. Increasing the causes the particles to have greater kinetic energy, allowing them to move faster and have a greater chance of reacting.
107. To balance an equation, what is placed in front of each component? Coefficient
108. Dispersions forces are found in which covalent bond? All (polar and non-polar)
109. The weakest of all intermolecular forces? Dispersion forces
110. A Dipole attraction is a intermolecular force? Weak
111. What is created when an electron pair in a covalent bond is shared unequally? Dipole
112. The attractions of one dipole to another is? Dipole interactions
113. Strongest bond of intermolecular forces?
Hydrogen bond (but weaker than ionic and covalent, which are intramolecular bonds)
114. Elements Flourine (F), Chlorine (Cl ), Oxygen (O) and Nitrogen (N) are involved in which bond?
115. Polarity is?
Based on the difference in electronegativity values for the elements involved
116. What reactions take place in the nucleus to obtain stable nuclear configurations? Nuclear reactions
117. Mass # - Atomic # = # Neutrons in an element
118. Protons + Neutrons = Mass #
119. # of Protons in an element = Atomic #
120. Neutral subatomic particles = Neutrons
121. – charge subatomic particles = electrons
122. + charge subatomic particles = Protons
123. Charge of noble gases? 0
124. Group IA = +1 Charge
125. Group IIA = +2 Charge
126. Group IIIA = +3 Charge
127. Group VA = -3 Charge
128. Group VIA = -2 Charge
129. Group VIIA = -1 Charge
130. Rows on periodic table:
Period (Horizontal Left/right) (remember: “R” and “P” look very similar)
131. Columns of periodic table:
Group (Vertical up/down) (remember: “C” and “G” look very similar)
132. How elements are arranged on the periodic table? By their chemical properties
133. Matter that has definite shape & volume? Solid
134. Matter that changes in volume with changes in temperature & pressure? Gas
135. Which change of matter is when no change is made to the chemical composition of a substance?
Physical (if the chemical composition changes, it’s a chemical change. Boiling water is physical because it’s H2O before and after. Changing H2O to H2 and O2 is a chemical change)
136. Simplest substance and is represented by a letter or letters? Element
137. Law that states matter can neither be created nor destroyed during a chemical reaction (but it can change forms)?
Law of conservation of mass
138. Law that states energy can neither be created nor destroyed (but it can change forms)? Law of conservation of energy
3- LI 4- BE 5 B 6- C N 7 0 8 F9 NE 10
11- NA 12- Mg 13- AL 14-SI 15-P 16-S 17-Cl 18-Ar
K- 19 CA- 20 [Show Less]