question stringlengths 4 296 | choices listlengths 4 4 | answer class label 4 classes | difficulty stringclasses 3 values |
|---|---|---|---|
Which oxide has the highest number of valence electrons? | [
"MgO",
"K2O",
"Al2O3",
"Na2O"
] | 2C | medium |
Write the balanced chemical equation for the reaction between the hypochlorite ion (ClO-) and H+ (aq). | [
"HOCl + H+ → Cl+ + H2O",
"ClO- + H+ → HOCl",
"ClO- + H+ → ClH + O",
"ClO- + H+ → Cl- + H2O"
] | 1B | medium |
What helps complete the circuit in the corrosion process? | [
"Carbonic acid.",
"Soot particles.",
"Carbon dioxide.",
"The iron itself."
] | 3D | hard |
What is the enthalpy change of the complete combustion of ethane if the enthalpy of formation of C2H6 is -84.7 kJ/mol and that of CO2 is -393.5 kJ/mol? | [
"-1638 kJ/mol",
"-1729 kJ/mol",
"-1824 kJ/mol",
"-1322 kJ/mol"
] | 0A | easy |
How do you indicate the position of a side chain in an alkane? | [
"Both options A and C",
"By adding a prefix to the parent name",
"By separating the side chain name from the parent name with a dash",
"Using the number assigned to the carbon atom to which it is attached"
] | 3D | medium |
What is the main difference between the initial and final setup for the experiment? | [
"Melting the lead bromide makes it easier to insert the electrodes",
"Heating the lead bromide allows the electrodes to penetrate deeper",
"Melting the lead bromide increases the rate of reaction",
"The use of a Bunsen burner changes the type of reaction occurring"
] | 3D | medium |
What type of reaction is the formation of citric acid from acetyl CoA and oxaloacetic acid? | [
"Condensation reaction",
"Addition reaction",
"Hydrolysis reaction",
"Esterification reaction"
] | 0A | easy |
How do we decide whether to reverse an equation when combining them using Hess's Law? | [
"We reverse the equation if the reaction has a negative ΔH° value.",
"We only reverse the equation if the reaction is endothermic.",
"We never reverse the equation.",
"We always reverse the equation."
] | 1B | medium |
What is aqua regia used to dissolve? | [
"Some nonmetals",
"Most metals",
"Gold and other noble metals",
"Only gold"
] | 2C | easy |
Why do elements on the left end of a period tend to form positive ions more easily than those on the right end? | [
"Due to higher electronegativity",
"Due to lower electronegativity",
"Due to smaller atomic radius",
"Due to larger atomic radius"
] | 3D | hard |
Which of the following statements about equilibrium is true? | [
"Equilibrium means that no reaction occurs.",
"Equilibrium indicates the end of a chemical reaction.",
"Equilibrium is achieved only at a specific temperature.",
"At equilibrium, there is no net change in the concentrations of reactants and products."
] | 3D | easy |
According to the octet rule, how many electrons do atoms typically require to achieve stability? | [
"6",
"8",
"4",
"2"
] | 1B | easy |
Which of the following is an incorrect representation of an alkane? | [
"CH3CH(CH3)2",
"CH3CH3",
"CH3CH2CH2CH3",
"CH3CH2CH3"
] | 1B | medium |
Which solution has a low concentration of dissolved ions? | [
"D - none of the above",
"C - the bulb does not glow",
"A - the bulb glows dimly",
"B - the bulb glows strongly"
] | 2C | medium |
When monitoring the volume of gas produced during a reaction, what can be measured? | [
"Temperature",
"Time",
"Pressure",
"Volume"
] | 1B | medium |
What is the characteristic feature of a covalent bond? | [
"Involves sharing of electrons between atoms.",
"None of the above",
"Involves attraction between oppositely charged ions.",
"Involves transfer of electrons between atoms."
] | 0A | easy |
What determines whether a chemical reaction is favourable or not? | [
"The signs of ΔH and ΔS.",
"The pressure of the system.",
"The concentration of reactants and products.",
"The activation energy required for the reaction."
] | 0A | easy |
In the reaction between mercury and oxygen, what occurs? | [
"The reaction neither releases nor absorbs heat.",
"The reaction absorbs heat.",
"The reaction releases heat.",
"There is insufficient information to determine the direction of heat transfer."
] | 2C | hard |
What is the main purpose of carrying out photosynthesis? | [
"To release oxygen and produce carbon dioxide",
"To absorb water and release oxygen",
"To break down glucose and release energy",
"To convert carbon dioxide into glucose"
] | 0A | medium |
How are electron shells represented in diagrams? | [
"By concentric circles",
"As solid spheres",
"Not shown graphically",
"By lines and arrows"
] | 0A | easy |
What is the molar mass of P4O10? | [
"200 g/mol",
"140 g/mol",
"220 g/mol",
"160 g/mol"
] | 3D | medium |
How can you determine the mass of the gas used by the lighter? | [
"By recording the air pressure in the room",
"By weighing the lighter after use",
"By measuring the volume of the gas",
"By subtracting the final mass of the lighter from its initial mass"
] | 3D | easy |
What type of interaction holds the two strands of DNA together? | [
"Ionic bond",
"Hydrogen bond",
"Polar covalent bond",
"Covalent bond"
] | 1B | hard |
A sample of nitrogen gas occupies 1.30 L at a pressure of 98.0 kPa and a temperature of 295 K. What is its final volume at standard temperature and pressure (STP)? | [
"1.20 L",
"1.30 L",
"1.15 L",
"1.25 L"
] | 2C | medium |
What is the overall cell reaction for a lead-acid battery when it is not being charged? | [
"2PbSO 4(s)+2H2O(/lscript)→Pb(s)+PbO 2(s)+4H+(aq)+2SO 42−(aq)",
"PbSO 4(s)+2H2O(/lscript)→Pb(s)+PbO 2(s)+4H+(aq)+2SO 42−(aq)",
"Pb(s)+PbO 2(s)+4H+(aq)+2SO 42−(aq)→2PbSO 4(s)+2H2O(/lscript)",
"None of the above"
] | 2C | medium |
According to the information given in the above figure, the anode of the galvanic cell is _______________. | [
"Cu(s)",
"–",
"Ag(s)",
"+"
] | 0A | easy |
What is combined with the equilibrium constant to form Ksp? | [
"The concentration of a gas",
"The concentration of a gas and a liquid",
"The concentration of a solid",
"The concentration of a liquid"
] | 2C | easy |
Why is melting considered an endothermic process? | [
"It has no effect on heat energy",
"It produces no heat energy",
"It releases heat energy",
"It absorbs heat energy"
] | 3D | easy |
At what condition is the boiling point of a liquid determined? | [
"When the liquid reaches a certain temperature.",
"When the liquid has evaporated completely.",
"When the vapor pressure of the liquid equals the atmospheric pressure.",
"When the liquid has boiled away completely."
] | 2C | hard |
What is the molar mass of a substance calculated by dividing the mass of a sample by the number of moles? | [
"Boiling point",
"Molar mass",
"Density",
"Volume"
] | 1B | easy |
What concept allows us to calculate the amount of substance required or produced in a chemical reaction? | [
"Stoichiometry",
"Kinetics",
"Thermodynamics",
"Electrochemistry"
] | 0A | easy |
Why is it necessary to subtract the mass of the container when calculating the mass of the nitrogen gas? | [
"Because the mass of the container is not included in the calculation of moles.",
"None of the above.",
"Because the mass of the container would affect the accuracy of the measurement.",
"Because the mass of the container affects the overall mass of the system."
] | 0A | easy |
How would you describe the strength of intermolecular forces compared to covalent bonds? | [
"Weaker",
"Equal",
"Stronger",
"Comparable"
] | 0A | medium |
How should sulfuric acid be written in a net ionic equation? | [
"H2SO4(aq)",
"H+(aq) and SO42-(aq)",
"H2SO4",
"HSO4-(aq)"
] | 1B | easy |
If 1.00 g of methanol is combusted, how much CO2 will be produced? | [
"0.376 g",
"0.188 g",
"0.563 g",
"0.750 g"
] | 0A | medium |
Which functional group characterizes ketones? | [
"Hydroxyl (-OH)",
"Amine (-NH2)",
"Carboxyl (-COOH)",
"Carbonyl (C=O)"
] | 3D | easy |
How does atmospheric pressure affect cooking time at high elevations? | [
"It decreases cooking time.",
"It depends on the type of food being cooked.",
"It increases cooking time.",
"It has no effect on cooking time."
] | 0A | medium |
How does the mass of the tube containing magnesium perchlorate change after the reaction? | [
"Decreases",
"Remains the same",
"Does not change",
"Increases"
] | 3D | hard |
What is the purpose of suspending the test tube containing sodium chloride in the flask containing silver nitrate solution? | [
"To measure the volume of the solution",
"To mix the solutions quickly",
"To allow the reaction to occur",
"To prevent contamination"
] | 1B | hard |
Why are batteries able to store chemical energy? | [
"Because they use nuclear reactions",
"Because they contain galvanic cells",
"Because they use combustion reactions",
"Because they use acid-base reactions"
] | 1B | hard |
What method would you use to find the empirical formula of a compound containing carbon, hydrogen, and oxygen? | [
"Spectroscopy",
"Combustion analysis",
"Chromatography",
"Titration"
] | 1B | medium |
What is the difference between the general formula for cycloalkanes and alkenes? | [
"The number of hydrogen atoms increases by 2.",
"The number of hydrogen atoms remains the same.",
"There is no difference in the general formula.",
"The number of hydrogen atoms decreases by 2."
] | 3D | hard |
What is the approximate bond angle between the tetrahedrally bonded atoms in alkanes? | [
"120°",
"90°",
"180°",
"109.5°"
] | 3D | easy |
What can be inferred about the rate of decomposition of sodium azide in an air bag compared to the rate of rust formation on a car? | [
"Both processes occur at the same rate.",
"Sodium azide decomposes slowly.",
"Sodium azide decomposes instantly, and rust forms slowly.",
"Rust forms instantly."
] | 2C | hard |
What factor affects the polarity of a molecule? | [
"All of the above",
"Bond length",
"Bond strength",
"Molecular shape"
] | 3D | medium |
Which of the following statements best describes the periodic table arrangement? | [
"It arranges elements by increasing electron affinity.",
"It arranges elements by increasing atomic mass.",
"It arranges elements by decreasing atomic number.",
"It arranges elements by increasing atomic radius."
] | 1B | hard |
Why is an efficient separation process necessary for extracting hydrocarbon components? | [
"So that we can conserve natural resources",
"To increase the amount of gas and oil found worldwide",
"Because petroleum is a complex mixture of hydrocarbons",
"So that we can produce more petroleum"
] | 2C | easy |
Which of the following statements about organic compounds is correct? | [
"All organic compounds contain only hydrogen and oxygen.",
"All organic compounds are derived from living organisms.",
"None of the above.",
"All organic compounds contain carbon as the main element."
] | 3D | medium |
What is an example of a physical change in the process of taking pictures? | [
"Changing the camera's focus",
"Printing a photograph",
"Exposing film to light",
"Mixing colors"
] | 2C | hard |
According to the text, which substance is being researched for its potential to superconduct? | [
"C. Diamonds.",
"B. Graphite.",
"A. Carbon nanotubes.",
"D. Water."
] | 2C | hard |
What is the significance of the suffix '-ene' in the naming of alkenes? | [
"It indicates the presence of a double bond",
"It indicates the presence of a triple bond",
"It indicates the presence of a single bond",
"It indicates the absence of a bond"
] | 0A | hard |
What type of model would be most suitable for representing the structure of a large biomolecule? | [
"Condensed structural diagram",
"Lewis structure",
"Ball-and-stick model",
"Space-filling model"
] | 3D | medium |
What is the process by which methane decomposes to deposit a thin film of diamond on a surface at 600°C and extremely low pressures? | [
"Chemical vapor deposition",
"Chemical vaporization",
"Electrochemical reaction",
"Chemical reaction"
] | 0A | easy |
An alloy is a homogeneous mixture of two or more _______________. | [
"Elements and compounds",
"Ionic and covalent compounds",
"Two or more metals",
"Metals and nonmetals"
] | 2C | hard |
What is the volume of 5.00 g of helium gas at standard temperature and pressure (STP)? | [
"22.4 L",
"44.8 L",
"67.2 L",
"89.6 L"
] | 0A | medium |
Which of the following particles has no charge? | [
"Ion",
"Electron",
"Neutron",
"Proton"
] | 2C | medium |
What is the number of moles of H2O in the hydrate Ba(OH)2·8H2O? | [
"8.0 mol",
"1.27 mol",
"10.0 mol",
"0.159 mol"
] | 1B | easy |
What is the term for the ability of a substance to act as both an acid and a base in different reactions? | [
"Basic behavior",
"Amphoteric",
"Acidic behavior",
"Electrophilic behavior"
] | 1B | easy |
What is the primary use of alkanes? | [
"As raw materials for making plastics",
"As fuels",
"As building blocks for other compounds",
"As solvents"
] | 1B | medium |
Why are pH meters or universal indicators used in this experiment? | [
"To monitor changes in pH levels.",
"To measure the concentration of ions in solution.",
"To observe the color change of a chemical reaction.",
"To determine the effect of temperature on chemical reactions."
] | 0A | easy |
According to Aristotle, what happens when a substance is broken down? | [
"it remains the same",
"it reaches the last indivisible particle",
"it disappears",
"it becomes continuous"
] | 3D | medium |
Ksp for PbCl2 is 1.7 × 10^-5. Based on the value of Qsp calculated earlier, does a precipitate form? | [
"No",
"Maybe",
"Yes",
"It depends on other factors"
] | 0A | easy |
Conjugate acids and bases are linked by the transfer of a _______________. | [
"Proton and Electron",
"Proton and Neutron",
"Electron and Neutron",
"Proton"
] | 3D | medium |
Which principle guides the order of filling energy levels and sublevels in the quantum mechanical model? | [
"Heisenberg Uncertainty Principle",
"Pauli Exclusion Principle",
"Aufbau Principle",
"Hund's Rule"
] | 2C | easy |
Which of the following properties are physical and which are chemical when comparing propane, butane, and paraffin? | [
"Physical - density, melting point, and boiling point; Chemical - heat of combustion",
"Physical - density and boiling point; Chemical - heat of combustion and melting point",
"Physical - heat of combustion and boiling point; Chemical - density and melting point",
"Physical - density and melting point; Chemical - heat of combustion and boiling point"
] | 0A | medium |
Which solution is being poured into the beaker in step 4 of the procedure? | [
"HNO3",
"None of these",
"nitric acid + acidified CuSO4",
"acidified CuSO4"
] | 3D | medium |
Write the products of the reaction between zinc (Zn) and copper(II) sulfate (CuSO4). | [
"Zn and CuSO4",
"Cu and ZnSO4",
"ZnSO4 and Cu",
"No reaction"
] | 1B | easy |
What is the term for the process where a nucleus emits an alpha particle? | [
"Gamma decay",
"Nuclear fission",
"Alpha decay",
"Beta decay"
] | 2C | hard |
What is the standard reduction potential (in volts) for the half-reaction Li+ (aq) + e- → Li(s)? | [
"-0.414 V",
"-3.040 V",
"1.066 V",
"0.815 V"
] | 1B | medium |
What is the role of the condenser in the Haber-Bosch process? | [
"To remove excess nitrogen gas",
"To increase the pressure inside the reaction vessel",
"To cool the gas mixture and separate ammonia",
"To add hydrogen gas to the mixture"
] | 2C | hard |
Which group includes calcium, gallium, and selenium? | [
"C) Group 16",
"D) Group 18",
"A) Group 1",
"B) Group 14"
] | 0A | easy |
What is the name and formula of the anion formed by hydrobromic acid? | [
"Nitrate ion, NO3-",
"Chloride ion, Cl-",
"Bromide ion, Br-",
"Hydroxide ion, OH-"
] | 2C | easy |
If 10.0 L of nitrogen gas at STP contains 0.444 mol, what is the mass of this gas sample? | [
"4.07 g",
"3.65 g",
"3.35 g",
"3.05 g"
] | 3D | medium |
In what process is carbon dioxide produced? | [
"Synthesis of ammonia",
"Combustion of carbon-containing compounds",
"Decomposition of hydrogen peroxide",
"Combustion of fossil fuels"
] | 1B | easy |
What is the role of carbon black in the electrolyte of a dry cell battery? | [
"It prevents corrosion",
"It helps conduct electricity",
"It stores energy",
"It adds color to the battery"
] | 1B | easy |
Will the aluminum electrode increase or decrease in mass as the galvanic cell operates? | [
"Increase",
"No change",
"Depends on the direction of electron flow",
"Decrease"
] | 3D | hard |
What is the maximum number of formula units of ZnS that can dissolve in 1.0 L of solution at 25°C? | [
"2.0 × 10^23",
"2.0 × 10^24",
"2.0 × 10^21",
"2.0 × 10^22"
] | 3D | medium |
Why is energy efficiency expressed as a percentage? | [
"It accounts for useful energy produced.",
"It measures energy used to extract and transport fuel.",
"It helps compare different energy sources.",
"It is easier to calculate."
] | 0A | hard |
In the Brønsted-Lowry theory, what happens when a substance receives a proton during an acid-base reaction? | [
"It becomes a gas.",
"It becomes an acid.",
"It becomes a salt.",
"It becomes a base."
] | 3D | medium |
According to the solubility guidelines, what is the solubility of AgNO3? | [
"Highly soluble",
"Moderate solubility",
"Very low solubility",
"Low solubility"
] | 3D | medium |
According to periodic trends, which of the following metals is likely to be the most reactive? | [
"Iron",
"Tin",
"Magnesium",
"Copper"
] | 2C | hard |
Which coefficient should be added to the aluminum atom in the equation Al(s) + O2(g) → Al2O3(s)? | [
"4",
"2",
"3",
"1"
] | 3D | medium |
How do noble gases contribute to the development of the octet rule? | [
"They have only one valence electron.",
"They are highly reactive and readily form bonds with other elements.",
"They never react with other elements.",
"Their full outer energy level has eight electrons."
] | 3D | medium |
What type of bond involves the attraction between positively and negatively charged ions? | [
"Hydrogen bond",
"Ionic bond",
"Van der Waals force",
"Covalent bond"
] | 1B | easy |
What is the term for a reaction that releases oxygen gas? | [
"Oxidation Reaction",
"Decomposition Reaction",
"Synthesis Reaction",
"Combustion Reaction"
] | 1B | medium |
How many gas molecules are present on the reactants' side of the given chemical equation: 2SO3(g) → 2SO2(g) + O2(g)? | [
"Five",
"Two",
"Four",
"Three"
] | 1B | medium |
Why does copper require two nitrate ions to balance its charge in the reaction Cu(s)+2AgNO3(aq)→Cu(NO3)2(aq)+2Ag? | [
"Because copper has a -2 charge",
"Because silver has a +2 charge",
"Because nitrate has a -2 charge",
"Because copper has a +2 charge"
] | 3D | medium |
How many liters of SO2 are produced if 5.3 L of O2 are consumed in the reaction: P + 4S -> P4O10 + SO2? | [
"10.6 L",
"1.33 L",
"2.66 L",
"5.3 L"
] | 0A | medium |
What is a diprotic acid? | [
"A base that contains two hydrogen ions that can dissociate",
"An acid that contains only one hydrogen ion that can dissociate",
"An acid that contains two hydrogen ions that can dissociate",
"An acid that does not dissociate at all"
] | 2C | easy |
What similarity do the Rutherford and Bohr atomic models share regarding the arrangement of electrons around the nucleus? | [
"They both suggest that electrons are arranged in a fixed path around the nucleus.",
"They both consider the nucleus as a positively charged sphere.",
"They both propose that electrons occupy specific energy levels.",
"They both ignore the wave-particle duality of electrons."
] | 2C | medium |
Is the combustion of hydrogen an exothermic reaction? | [
"No",
"Maybe",
"Not applicable",
"Yes"
] | 3D | medium |
How is pOH related to the hydroxide ion concentration? | [
"pOH = –log [OH–]",
"pOH = 1/[OH–]",
"pOH = [OH–]",
"pOH = log [OH–]"
] | 0A | easy |
What are reaction intermediates in the context of elementary reactions? | [
"Substances that are consumed in the first step of a reaction",
"None of these",
"Molecules or ions formed in an elementary reaction and consumed in a subsequent step",
"Substances that are formed in the final step of a reaction"
] | 2C | medium |
In a molecule, what relationship exists between bond strength and stability? | [
"Stronger bonds lead to more stable molecules",
"Weaker bonds lead to more stable molecules",
"Stronger bonds lead to less stable molecules",
"Weaker bonds lead to less stable molecules"
] | 0A | medium |
What type of reaction is CCl4 + HF → CFCl3 + HCl? | [
"Redox reaction",
"Combustion reaction",
"Decomposition reaction",
"Synthesis reaction"
] | 0A | medium |
According to Table 4.2, what is the VSEPR notation for CH4? | [
"AX3E",
"AX4",
"AX2E2",
"AX5"
] | 1B | medium |
To identify a redox reaction, what should you look for in a balanced chemical equation? | [
"Only oxidation occurring",
"Neither oxidation nor reduction occurring",
"Only reduction occurring",
"Both oxidation and reduction occurring"
] | 3D | easy |
Why are the elements in the d-block referred to as transition elements? | [
"Because they mark the transition from s-orbital filling to d-orbital filling.",
"Because they are highly reactive.",
"Because they have low atomic numbers.",
"Because they exhibit unique magnetic properties."
] | 0A | easy |
What do you call a molecule that acts as a building block for a polymer? | [
"Monomer",
"Polymer",
"Compound",
"Mixture"
] | 0A | easy |
According to Table 1.5, what happens when rounding an answer that ends in a number greater than 5? | [
"round up to the nearest hundredth",
"round down to the nearest whole number",
"increase the preceding digit by 1",
"leave the preceding digit unchanged"
] | 2C | medium |
End of preview. Expand
in Data Studio
README.md exists but content is empty.
- Downloads last month
- 5