CSET Multiple Subjects Subtest II –
Science: Chemistry, Physics and
Astronomy | Questions & Answers | 100%
Correct | Update
Chemistry (36 Multiple-Choice, 4 Constructed-Response)
Multiple-Choice Questions
Which element has the atomic number 6?
Hydrogen, Carbon, Nitrogen, Oxygen
Answer: Carbon
Explanation: The atomic number represents the number of protons in an atom’s nucleus.
Carbon has 6 protons, corresponding to atomic number 6 on the periodic table.
What type of bond involves the sharing of electrons?
Ionic, Covalent, Metallic, Hydrogen
Answer: Covalent
Explanation: Covalent bonds form when atoms share electrons to achieve stable electron
configurations, as in molecules like H₂O.
What is the pH of a neutral solution at 25°C?
0, 7, 14, 10
Answer: 7
Explanation: A neutral solution has equal concentrations of H⁺ and OH⁻ ions, resulting
in a pH of 7 at 25°C.
Which gas is the most abundant in Earth’s atmosphere?
Oxygen, Nitrogen, Carbon dioxide, Argon
Answer: Nitrogen
Explanation: Nitrogen constitutes approximately 78% of Earth’s atmosphere by volume.
,What is the chemical formula for water?
H₂O, CO₂, O₂, H₂
Answer: H₂O
Explanation: Water is composed of two hydrogen atoms and one oxygen atom,
represented as H₂O.
Which element is a noble gas?
Sodium, Helium, Chlorine, Magnesium
Answer: Helium
Explanation: Noble gases, found in Group 18 of the periodic table, are inert due to full
valence electron shells. Helium is a noble gas.
What type of reaction releases heat?
Endothermic, Exothermic, Neutralization, Decomposition
Answer: Exothermic
Explanation: Exothermic reactions release heat to the surroundings, increasing the
temperature (e.g., combustion).
What is the mass number of an atom with 8 protons and 8 neutrons?
8, 16, 24, 32
Answer: 16
Explanation: Mass number = protons + neutrons = 8 + 8 = 16.
Which substance is an acid?
NaOH, HCl, KOH, NH₃
Answer: HCl
Explanation: Acids donate H⁺ ions in solution. HCl (hydrochloric acid) is a strong acid.
What is the charge of a proton?
Positive, Negative, Neutral, Variable
Answer: Positive
Explanation: Protons carry a positive charge, balancing the negative charge of electrons
in an atom.
, Which element has the symbol Fe?
Fluorine, Iron, Francium, Fermium
Answer: Iron
Explanation: Fe is the chemical symbol for iron on the periodic table.
What type of bond forms between sodium and chlorine in NaCl?
Covalent, Ionic, Metallic, Hydrogen
Answer: Ionic
Explanation: Ionic bonds form between metals (Na) and nonmetals (Cl) via electron
transfer, creating charged ions.
What is the molar mass of CO₂?
12 g/mol, 32 g/mol, 44 g/mol, 56 g/mol
Answer: 44 g/mol
Explanation: C = 12 g/mol, O = 16 g/mol. CO₂ = 12 + (2 × 16) = 44 g/mol.
Which is a physical change?
Burning wood, Rusting iron, Melting ice, Digesting food
Answer: Melting ice
Explanation: Physical changes alter form without changing chemical composition.
Melting ice changes state but remains H₂O.
What is the atomic number of oxygen?
6, 8, 10, 12
Answer: 8
Explanation: Oxygen has 8 protons, corresponding to its atomic number.
Which gas is produced during photosynthesis?
Carbon dioxide, Oxygen, Nitrogen, Hydrogen
Answer: Oxygen
Explanation: Photosynthesis produces oxygen as a byproduct when plants convert CO₂
and water into glucose.
Science: Chemistry, Physics and
Astronomy | Questions & Answers | 100%
Correct | Update
Chemistry (36 Multiple-Choice, 4 Constructed-Response)
Multiple-Choice Questions
Which element has the atomic number 6?
Hydrogen, Carbon, Nitrogen, Oxygen
Answer: Carbon
Explanation: The atomic number represents the number of protons in an atom’s nucleus.
Carbon has 6 protons, corresponding to atomic number 6 on the periodic table.
What type of bond involves the sharing of electrons?
Ionic, Covalent, Metallic, Hydrogen
Answer: Covalent
Explanation: Covalent bonds form when atoms share electrons to achieve stable electron
configurations, as in molecules like H₂O.
What is the pH of a neutral solution at 25°C?
0, 7, 14, 10
Answer: 7
Explanation: A neutral solution has equal concentrations of H⁺ and OH⁻ ions, resulting
in a pH of 7 at 25°C.
Which gas is the most abundant in Earth’s atmosphere?
Oxygen, Nitrogen, Carbon dioxide, Argon
Answer: Nitrogen
Explanation: Nitrogen constitutes approximately 78% of Earth’s atmosphere by volume.
,What is the chemical formula for water?
H₂O, CO₂, O₂, H₂
Answer: H₂O
Explanation: Water is composed of two hydrogen atoms and one oxygen atom,
represented as H₂O.
Which element is a noble gas?
Sodium, Helium, Chlorine, Magnesium
Answer: Helium
Explanation: Noble gases, found in Group 18 of the periodic table, are inert due to full
valence electron shells. Helium is a noble gas.
What type of reaction releases heat?
Endothermic, Exothermic, Neutralization, Decomposition
Answer: Exothermic
Explanation: Exothermic reactions release heat to the surroundings, increasing the
temperature (e.g., combustion).
What is the mass number of an atom with 8 protons and 8 neutrons?
8, 16, 24, 32
Answer: 16
Explanation: Mass number = protons + neutrons = 8 + 8 = 16.
Which substance is an acid?
NaOH, HCl, KOH, NH₃
Answer: HCl
Explanation: Acids donate H⁺ ions in solution. HCl (hydrochloric acid) is a strong acid.
What is the charge of a proton?
Positive, Negative, Neutral, Variable
Answer: Positive
Explanation: Protons carry a positive charge, balancing the negative charge of electrons
in an atom.
, Which element has the symbol Fe?
Fluorine, Iron, Francium, Fermium
Answer: Iron
Explanation: Fe is the chemical symbol for iron on the periodic table.
What type of bond forms between sodium and chlorine in NaCl?
Covalent, Ionic, Metallic, Hydrogen
Answer: Ionic
Explanation: Ionic bonds form between metals (Na) and nonmetals (Cl) via electron
transfer, creating charged ions.
What is the molar mass of CO₂?
12 g/mol, 32 g/mol, 44 g/mol, 56 g/mol
Answer: 44 g/mol
Explanation: C = 12 g/mol, O = 16 g/mol. CO₂ = 12 + (2 × 16) = 44 g/mol.
Which is a physical change?
Burning wood, Rusting iron, Melting ice, Digesting food
Answer: Melting ice
Explanation: Physical changes alter form without changing chemical composition.
Melting ice changes state but remains H₂O.
What is the atomic number of oxygen?
6, 8, 10, 12
Answer: 8
Explanation: Oxygen has 8 protons, corresponding to its atomic number.
Which gas is produced during photosynthesis?
Carbon dioxide, Oxygen, Nitrogen, Hydrogen
Answer: Oxygen
Explanation: Photosynthesis produces oxygen as a byproduct when plants convert CO₂
and water into glucose.
