Year 9 Chemical Reactions: Properties, Equations, and Energy Changes Practice Test

These questions are part of the practice quiz. Start practicing

• Litmus test: how can you distinguish acids and bases using litmus paper? What colors indicate each?
• What does it mean for a chemical equation to be balanced, and what must be the same on both sides?
• Which precipitate forms when BaCl2 is mixed with H2SO4?
• Which substance acts as a base in this reaction?
• Which statement describes a precipitation reaction?
• Which statement best describes a synthesis reaction?
• Which indicator is commonly used to determine neutralization end-points in acid-base titrations?
• The term 'energy transfer' in chemistry refers to which of the following?
• What misconception might students have about pH?
• Which statement best defines a decomposition reaction?
• Which is an everyday endothermic reaction?
• What is pH?
• A universal indicator shows pH 2. Is the solution acidic or basic, and what is a typical color range for that pH?
• What is the decomposition reaction of calcium carbonate when heated, and what gas is produced?
• What does a chemical equation convey?
• When Pb(NO3)2 is mixed with KI, a yellow precipitate forms. What is the color of the precipitate?
• In the net ionic equation for the formation of BaSO4, which ions participate?
• In a reaction where solid calcium carbonate is heated to release CO2 and CaO, what is the type of reaction and the products?
• Which statement about temperature and reaction rate is true?
• What is a chemical symbol?
• What does the arrow in a chemical equation indicate about the relationship between reactants and products?
• Which of the following is an observable sign of an acid-metal reaction that is commonly expected in experiments?
• What happens to reaction rate if a solid reactant is ground into powder?
• A balanced chemical equation is one that:
• State the calorimetry formula used to calculate energy change in a simple solution heating/cooling experiment.
• In chemical reactions, how is energy typically transferred?
• When mixing sodium sulfate with barium chloride, what precipitate forms, and write the net ionic equation.
• If 1 mole of Na2CO3 reacts with 4 moles of HCl, which reactant is in excess after the reaction is complete?
• What is the general effect of increasing pressure on the reaction rate for gas-phase reactions?
• In the reaction Na2CO3 + 2 HCl -> 2 NaCl + H2O + CO2, which salt is formed besides water and carbon dioxide?
• Which term describes the starting substances in a chemical reaction?
• What do you call a reaction that absorbs heat from the surroundings?
• Which of the following is a product of complete combustion of hydrocarbons?
• How does surface area affect reaction rate?
• Which term best describes a reaction where a fuel reacts with oxygen to produce heat and light?
• What is a displacement reaction?
• What observable evidence indicates a reaction between acids and metals?
• What is a balanced equation?
• Which statement correctly distinguishes exothermic and endothermic reactions, with an everyday example for each?
• What is neutralization?
• State the general word equation for a metal reacting with an acid to produce a salt and hydrogen gas.
• Which metal is higher in the reactivity series and can displace copper from a compound in solution?
• What does a word equation help communicate in chemistry?
• Name three factors that can increase the rate of a chemical reaction and briefly explain how they do so.
• What is combustion?
• When an acid reacts with a carbonate, which gas is typically released?
• Which statement best describes the difference between physical changes and chemical changes?
• What is the conservation of atoms in a chemical reaction?
• When calcium carbonate reacts with hydrochloric acid, which gas is produced and how can you test for it?
• Which is the net ionic equation for Pb(NO3)2 + 2 KI → PbI2(s) + 2 KNO3?
• What role does MnO2 play in the decomposition of hydrogen peroxide?
• What is formed when a metal burns in oxygen? Give a general example.
• Which is a common household item related to acids and bases?
• In the reaction between sodium carbonate and hydrochloric acid, which gas is released?
• What are the general products of a neutralization reaction between an acid and a base?
• In collision theory, what is activation energy?
• In a chemical equation, what do the stoichiometric coefficients represent?
• Which gas is produced in the decomposition of hydrogen peroxide catalyzed by MnO2?
• If mixing two aqueous ionic solutions forms a white precipitate, what does this indicate about the ions?
• What is a chemical reaction?
• Which of the following is a sign that combustion is occurring?
• What is a precipitation rule, and how is it used to predict whether a precipitate will form?
• Why is precise language important in chemistry?
• Which equation represents the balanced combustion of methane?
• Which are everyday exothermic reactions?
• What type of reaction occurs when a soluble salt reacts to form a precipitate?
• Why are spectator ions removed when forming a net ionic equation?
• Which of the following is a product of the reaction between sodium carbonate and hydrochloric acid?
• A dissolution process is tested for temperature change. How can you determine whether it is endothermic or exothermic?
• What is a word equation?
• When BaCl2 solution is mixed with H2SO4, what is the precipitate that forms and what is the other product?
• What type of reaction occurs when sodium carbonate reacts with hydrochloric acid?
• What is the balanced symbol equation for the complete combustion of methane in oxygen to form carbon dioxide and water?
• Using the activity series, will copper displace silver from AgNO3 in solution?
• Which scientist is known for standardizing chemical symbols and formulas?
• Which term describes a reaction in which one element takes electrons from another?
• Define solute and solvent, and give an example in a salt solution.
• Distinguish between a word equation and a symbol (chemical) equation.
• In an exothermic reaction, the energy of the products compared to the reactants is:
• Which statement correctly describes how a catalyst affects a reaction?
• Which products are produced in a neutralization reaction between an acid and a base?
• Why is the law of conservation of mass still valid when a gas is produced in a reaction carried out in a closed container?
• Which of the following is true about the vocabulary used to describe a reaction that releases energy?
• What does the term 'reactivity' refer to in chemistry?
• Which is an everyday example of an endothermic reaction?
• What role does a catalyst play in a reaction, and does it affect yield?
• Which scenario demonstrates accurate use of scientific vocabulary?
• Which collection method provides direct measurement of gas volume in a classroom setting?
• Why is interpreting temperature data in reactions significant?
• A catalyst provides an alternative reaction pathway with what effect on activation energy?
• What is kaitiakitanga in the context of chemical use?
• If 0.5 moles Na2CO3 react completely, how many moles NaCl are produced?
• When an ionic compound dissolves in water, the ions that form are called
• How does concentration affect reaction rate?
• In a precipitation reaction, which species are removed to form the net ionic equation?
• Which balanced equation represents the neutralization of sulfuric acid with sodium hydroxide?
• What is an electrolyte, and give an example of an electrolyte and a non-electrolyte?
• How does increasing surface area influence reaction rate, and why?
• Which of the following is not a product of the reaction?
• What does the law of conservation of mass state?
• What is a reactant?
• When sulfuric acid reacts with sodium carbonate, what is the balanced chemical equation?
• Which statement is true about complete combustion?
• Incomplete combustion of a hydrocarbon often produces which pollutant?
• What is the oxide formed when magnesium burns in air?
• What is the role of indicators in classifying solutions?
• Which statement best describes mass conservation in chemical reactions?
• Which statement about alkalis is true?
• What observation would you expect when two soluble salts react to form an insoluble salt (a precipitate)?
• What are the key components of combustion?
• What is the chemical formula for the salt formed in this reaction?
• In a closed system, mass is conserved because:
• Why is controlling combustion important?
• Which statement describes the effect of a catalyst on a reaction's activation energy?
• How is the energy change of a reaction calculated using bond energies?
• Write the balanced equation for the combustion of propane (C3H8).
• Activation energy is defined as the minimum energy required for reactants to collide and form products; what role does it play in reaction rate?
• Which statement about balanced equations is true?
• How can students identify exothermic and endothermic reactions?
• In a displacement reaction, what happens?
• Which term describes a solid that forms and settles out of a liquid mixture during a chemical reaction?
• Write the balanced neutralization equation for sulfuric acid neutralizing sodium hydroxide.
• When balancing equations, why might you avoid using fractional coefficients?
• How can you tell from an energy diagram whether a reaction is exothermic or endothermic?
• Predict the type of reaction for Mg reacting with HCl and provide the balanced equation.
• Which observation would most strongly indicate that a displacement reaction has occurred in a metal solution?
• What is the reactivity series?
• What do you call a reaction that releases heat to the surroundings?
• Which statement best distinguishes a chemical change from a physical change?
• What is the net ionic equation for the reaction between Na2SO4 and BaCl2 in aqueous solution, which forms a precipitate?
• Which description best fits an exothermic reaction in a calorimeter?
• Balance the equation: H2 + O2 -> H2O.
• The reaction releases energy; what is this energy change called?
• Which balanced equation represents the reaction of calcium with water to form calcium hydroxide and hydrogen gas?
• Using the bond-energy method, if 100 kJ of bonds are broken and 80 kJ of bonds are formed, what is the energy change?
• Write the balanced equation for the decomposition of hydrogen peroxide catalyzed by a catalyst (e.g., MnO2).
• What is the full ionic equation for Pb(NO3)2 + 2 KI → PbI2(s) + 2 KNO3?
• In the balanced equation Na2CO3 + 2 HCl → 2 NaCl + CO2 + H2O, what is the coefficient of HCl?
• In a calorimetry calculation, if 50 g of water is heated from 20°C to 30°C with specific heat capacity c = 4.18 J/g°C, what is the energy absorbed?
• Which gas is released when Na2CO3 reacts with HCl?
• What is activation energy?
• In the reaction of zinc with dilute sulfuric acid, which gas is produced?
• If a reaction releases heat, what is the sign of ΔH, and how would this appear on an energy profile diagram?
• How can hydrogen gas be tested in the lab?
• How many letters can a chemical symbol contain?
• Which statement correctly describes an exothermic reaction?
• What is an alkali?
• What should students do to present observations and data?
• Complete combustion of methane yields which products?
• Which of the following is a sign that a chemical reaction has produced a gas?
• Which statement correctly describes the solubility of nitrates in water?
• Which qualitative test demonstrates the production of carbon dioxide in a reaction?
• Differentiate between complete and incomplete combustion of a hydrocarbon and name a typical product of incomplete combustion.
• What is an exothermic reaction?
• What are the products of complete combustion of a hydrocarbon?
• What is calorimetry?
• What common household items are connected to acids and bases?
• What is the purpose of using word equations in chemistry?
• What does it mean if a substance dissolves in a solution?
• Balance the equation: H2 + O2 -> H2O.
• In the displacement reaction Fe(s) + CuSO4(aq) → FeSO4(aq) + Cu(s), which species is reduced?
• What defines a precipitation reaction?
• Which of the following would indicate a displacement reaction?
• Which gas is produced when calcium carbonate decomposes upon heating?
• What best defines a displacement reaction?
• Name a common method to collect a gas produced in a school experiment and state one advantage.
• In neutralization, what are the products?
• Balance the formation of water: 2 H2 + O2 → ?
• In an exothermic reaction, which statement is true?
• In the reaction between AgNO3 and NaCl, which ions combine to form the precipitate?
• Which of the following is a neutralization reaction?
• Provide a balanced equation for the complete combustion of ethene (C2H4).
• What is the objective of Learning Phase 4 regarding acids and bases?
• In calorimetry, the expression q = m c ΔT calculates the energy change for which component?
• What is a common misconception about energy in reactions?
• What are the main products of complete combustion of a hydrocarbon?
• Which statement about energy transfer in chemical reactions is accurate?
• In a synthesis reaction, two or more substances combine to form what?
• Which test would confirm that CO2 is produced during the reaction?
• Which statement describes an endothermic reaction?
• What describes an endothermic reaction?
• If a chemical reaction causes the surroundings to become warmer, is the reaction exothermic or endothermic? Why?
• Which statement about displacement reactions is true?
• What are the products of complete combustion of hydrocarbons?
• Balance the equation Fe + O2 -> Fe2O3.
• Write the balanced symbol equation for the neutralization of hydrochloric acid with sodium hydroxide.
• What is the role of coefficients in a chemical equation?
• Which is an example of an endothermic process?
• What is the effect of a catalyst on a reaction rate diagram?
• In a calorimeter, a reaction releases 1500 J of heat to the surroundings in a 100 g water calorimeter with c = 4.18 J/g°C. What is the resulting temperature rise of the water?
• If in a reaction the energy released in forming bonds is greater than the energy required to break bonds, what is the overall energy change and is the reaction exothermic or endothermic?
• What is a balanced chemical equation?
• Which of the following is true about a balanced equation?
• What are the products of complete combustion of methane?
• Explain why energy is released or absorbed during a chemical reaction in terms of bonds breaking and forming.
• What evidence can indicate that a displacement reaction has occurred?
• What is a chemical formula?
• Explain why increasing temperature generally increases the rate of a chemical reaction.
• What is the difference between a chemical equation and a word equation?
• Why is mass conserved in a chemical reaction?
• Which statement best describes the role of scientific vocabulary in communicating energy changes?
• In a simple mass–mass reaction scenario, how can you determine the limiting reactant?
• In a single-displacement reaction where iron displaces copper from copper(II) sulfate, which is the net ionic equation?
• In a decomposition reaction, a compound breaks down into what?
• What is the mole ratio of CO2 produced to Na2CO3 consumed in the balanced equation?
• If 2 moles Na2CO3 react completely, how many moles NaCl are produced?
• What gas is produced when calcium reacts with water?
• Which statement best defines an exothermic reaction?
• Which of the following indicates a chemical change, not just a physical change?
• Which of the following involves oxidation state changes?
• What is the term for a reaction that can proceed in both forward and reverse directions, and is this common in Year 9 content?
• When silver nitrate and potassium chloride react, what is the precipitate, and what is the net ionic equation?
• Which factors can cause the theoretical yield to differ from the actual yield in a reaction?
• What does the arrow in a chemical equation represent?
• Which statement about energy transfer is accurate?
• Which of the following is a sign that a chemical reaction has occurred?
• If 418 J of heat is added to 100 g of water with a specific heat capacity of 4.18 J/g°C, what is the resulting temperature rise?
• Define a precipitate and describe how you would know one has formed in a reaction mixture.
• In a redox reaction, what is transferred between species, and how can you identify a redox change?
• Which statement is a common misconception about chemical reactions?
• What term describes a solid formed from two aqueous solutions?
• Why are lab safety routines important in chemical reactions?
• What is the balanced equation for the reaction of zinc with sulfuric acid to produce zinc sulfate and hydrogen gas?
• Balance the equation Al + Fe2O3 -> Al2O3 + Fe.
• What is a chemical formula?
• The reaction between silver nitrate and sodium chloride is an example of which type of reaction?
• What is an acid?
• Which of the following is a product of complete combustion of a hydrocarbon?
• What is the formula of the salt formed when HCl neutralizes NaOH?
• Which statement about physical changes is true?
• How does a catalyst affect activation energy and reaction rate?
• Which balanced equation correctly represents the combustion of methane in oxygen to form carbon dioxide and water?
• Which ions from the reactants end up in the main salt formed in solution?
• Which term best describes a reaction where a fuel reacts with oxygen?
• What is a spectator ion?
• What is the state of CO2 at room temperature in this context?
• Which ions are the spectator ions in the reaction Pb(NO3)2 + 2 KI → PbI2(s) + 2 KNO3?
• Which term describes a substance formed as a result of a chemical reaction?
• Which equation represents a synthesis reaction?
• Describe the balanced chemical equation for the reaction of sodium with water.
• What is the net ionic equation for the reaction between silver nitrate and sodium chloride in aqueous solution?
• What is the significance of temperature change in chemical reactions?
• What is a product?
• What is a precipitate?
• What is the role of scientific vocabulary in chemistry?
• Which statement best describes an endothermic process?
• In the reaction between silver nitrate and sodium chloride, what happens to the sodium ions (Na+) after the reaction?
• How would you test for carbon dioxide gas produced in a reaction mixture?
• In a neutralization reaction between an acid and a base, what is typically formed?
• Which statement best defines an endothermic reaction?
• When balancing chemical equations, why are polyatomic ions like OH- or SO4^2- often kept together on both sides?
• Who is Jöns Jakob Berzelius?
• What is the balanced decomposition equation for hydrogen peroxide catalyzed to water and oxygen?
• What is a base?