Kitchen Chemistry Review Chemical Reactions, Role of Baking Ingredients, Biochemicals, Acids and Bases Chemical Reactions Be able to recognize if a change is physical or chemical, giving reasons why. Physical: Change in shape, size, state or amount Chemical: Change in chemical composition, new substance is made. Be able to recognize if a change is physical or chemical, giving reasons why. Physical: Change in shape, size, state or amount Chemical: Change in chemical composition, new substance is made. Physical and Chemical Changes https://www.quia.com/quiz/ html https://www.quia.com/quiz/ html https://www.quia.com/quiz/ html https://www.quia.com/quiz/ html Parts of an Equation Practice Questions 1. A substance that enters into a chemical reaction is called a a. mole. c. coefficient. b. product. d. reactant. Answer: D 1. A substance that enters into a chemical reaction is called a a. mole. c. coefficient. b. product. d. reactant. Answer: D Practice Questions In a reaction in which hydrogen reacts with oxygen to produce water, which substances are the reactants? a. hydrogen only c. both hydrogen and oxygen b. oxygen only d. water Answer: C In a reaction in which hydrogen reacts with oxygen to produce water, which substances are the reactants? a. hydrogen only c. both hydrogen and oxygen b. oxygen only d. water Answer: C Practice Questions In a chemical equation, the symbol that takes the place of the word yields is a(n) a. equal sign. c. plus sign. b. coefficient. d. arrow. In a chemical equation, the symbol that takes the place of the word yields is a(n) a. equal sign. c. plus sign. b. coefficient. d. arrow. Practice Questions When oxygen is available, sulfur dioxide is produced from the burning of sulfur. Which of the following word equations best represents this reaction? a. sulfur + oxygen => sulfur dioxide b. sulfur dioxide + oxygen =>sulfur c. sulfur dioxide = >sulfur + oxygen d. sulfur => sulfur dioxide + oxygen Answer: A When oxygen is available, sulfur dioxide is produced from the burning of sulfur. Which of the following word equations best represents this reaction? a. sulfur + oxygen => sulfur dioxide b. sulfur dioxide + oxygen =>sulfur c. sulfur dioxide = >sulfur + oxygen d. sulfur => sulfur dioxide + oxygen Answer: A Practice Questions The word equation magnesium reacts with chlorine to produce magnesium chloride would be represented by which of the following formula equations? a. Mg => Cl 2 + MgCl 2 b. MgCl 2 => Mg+ Cl 2 c. MgCl 2 + Mg => Cl 2 d. Mg + Cl 2 =>MgCl 2 Answer: D The word equation magnesium reacts with chlorine to produce magnesium chloride would be represented by which of the following formula equations? a. Mg => Cl 2 + MgCl 2 b. MgCl 2 => Mg+ Cl 2 c. MgCl 2 + Mg => Cl 2 d. Mg + Cl 2 =>MgCl 2 Answer: D Practice Questions The symbol ( s ) written after a formula in a chemical equation stands for a. soluble. c. solid. b. solution. d. synthesis. Answer: C The symbol ( s ) written after a formula in a chemical equation stands for a. soluble. c. solid. b. solution. d. synthesis. Answer: C Practice Questions Which of the following symbols means a substance is in water solution? a. ( aq ) c. ( w ) b. ( s ) d. ( l ) Answer: A Which of the following symbols means a substance is in water solution? a. ( aq ) c. ( w ) b. ( s ) d. ( l ) Answer: A Be able to identify the 5 types of chemical reactions Synthesis:A + B=> AB Decomposition: AB => A + B Combustion: Chemical + oxygen carbon dioxide + watercarbon dioxide Single Displacement (Replacement) A + BC => AB + C Double Displacement (Replacement) AB + CD => AC + BD Synthesis:A + B=> AB Decomposition: AB => A + B Combustion: Chemical + oxygen carbon dioxide + watercarbon dioxide Single Displacement (Replacement) A + BC => AB + C Double Displacement (Replacement) AB + CD => AC + BD Practice Questions What kind of reaction is represented by the equation C 2 C l4 + Cl 2 => C2C l6 ? a. synthesis c. single replacement b. double replacement d. combustion Answer: A What kind of reaction is represented by the equation C 2 C l4 + Cl 2 => C2C l6 ? a. synthesis c. single replacement b. double replacement d. combustion Answer: A Practice Questions The reaction 2Mg( s ) + O 2 ( g ) H 2 ( g ) + MgC l2 ( aq ) is a a. composition reaction. c. single-replacement reaction. b. decomposition reaction. d. double-replacement Answer: C Practice Questions The reaction Pb(NO 3 ) 2 ( aq ) + 2KI( aq ) => PbI 2 ( s ) + 2KNO3( aq ) is a a. double-replacement reaction. c. decomposition reaction. b. synthesis reaction. d. combustion reaction. Answer: A The reaction Pb(NO 3 ) 2 ( aq ) + 2KI( aq ) => PbI 2 ( s ) + 2KNO3( aq ) is a a. double-replacement reaction. c. decomposition reaction. b. synthesis reaction. d. combustion reaction. Answer: A Law of Conservation of Mass (Matter) Atoms can be neither created nor destroyed in a chemical reaction. Number of atoms on reactant side = Number on product side Mass stays the same Atoms can be neither created nor destroyed in a chemical reaction. Number of atoms on reactant side = Number on product side Mass stays the same Practice Questions To balance a chemical equation, it may be necessary to adjust the a. coefficients. c. formulas of the products. b. subscripts. d. number of products. Answer: A To balance a chemical equation, it may be necessary to adjust the a. coefficients. c. formulas of the products. b. subscripts. d. number of products. Answer: A Practice Questions According to the law of conservation of mass, the total mass of the reacting substances is a. always more than the total mass of the products. b. always less than the total mass of the products. c. sometimes more and sometimes less than the total mass of the products. d. always equal to the total mass of the products. Answer: D According to the law of conservation of mass, the total mass of the reacting substances is a. always more than the total mass of the products. b. always less than the total mass of the products. c. sometimes more and sometimes less than the total mass of the products. d. always equal to the total mass of the products. Answer: D Practice Questions P + O 2 P 4 O 10 Is this equation balanced? Yes / No Answer : No P + O 2 P 4 O 10 Is this equation balanced? Yes / No Answer : No Practice Questions 4 Fe + 3O 2 2 Fe 2 O 3 Fe =Fe = O =O = Is this equation balanced? Yes / No Answer: Yes 4 Fe + 3O 2 2 Fe 2 O 3 Fe =Fe = O =O = Is this equation balanced? Yes / No Answer: Yes Practice Questions 2(NH 4 ) 2 +Cr 2 O 7 How many of each element are there? Answer: 4N16H2Cr7 O 2(NH 4 ) 2 +Cr 2 O 7 How many of each element are there? Answer: 4N16H2Cr7 O Baking Ingredients Be able to identify the role of baking ingredients: Sugar tenderizer, adds moistness, causes browning Salt Adds flavor, Controls reaction of yeast Leavening Agents: Produce CO 2, pushing dough or batter up as the gas tries to escape Egg whites serves as leavening agent as air is whipped into whites Be able to identify the role of baking ingredients: Sugar tenderizer, adds moistness, causes browning Salt Adds flavor, Controls reaction of yeast Leavening Agents: Produce CO 2, pushing dough or batter up as the gas tries to escape Egg whites serves as leavening agent as air is whipped into whites Baking Ingredients Egg Yolks add flavor and tenderness Milk Add nutrients, helps objects brown, activates reactions as a liquid Flour binds ingredients together, protein (gluten) is developed with stirring, More protein chewier product is Egg Yolks add flavor and tenderness Milk Add nutrients, helps objects brown, activates reactions as a liquid Flour binds ingredients together, protein (gluten) is developed with stirring, More protein chewier product is Practice Questions What baking ingredient is responsible for browning of baked goods? A.SaltB. SugarC. FlourD. Leavening Agent Answer: B What baking ingredient is responsible for browning of baked goods? A.SaltB. SugarC. FlourD. Leavening Agent Answer: B Practice Questions Which of the following is NOT a leavening agent? A.Baking SodaB. Baking PowderC. Egg Whites D. Cream of Tartar Answer: D Which of the following is NOT a leavening agent? A.Baking SodaB. Baking PowderC. Egg Whites D. Cream of Tartar Answer: D Practice Questions You are baking muffins. When it comes out of the oven, you notice that there are lots of holes in the muffins. What might have happened? A.Too much leavening agent was added B.It was cooked at too hot of a temperature C.Too much sugar was added D.Too much fat was added Answer: A You are baking muffins. When it comes out of the oven, you notice that there are lots of holes in the muffins. What might have happened? A.Too much leavening agent was added B.It was cooked at too hot of a temperature C.Too much sugar was added D.Too much fat was added Answer: A Practice Questions If cooking loaf bread, what type of flour would be best? A.One with a high amount of protein B.One with a small amount of protein C.One with no protein D.It doesnt matter Answer: A If cooking loaf bread, what type of flour would be best? A.One with a high amount of protein B.One with a small amount of protein C.One with no protein D.It doesnt matter Answer: A Practice Questions Your cookies have coagulated. What has happened? A. They have turned brown B. The sugar has melted and is syrup-lik C. The water has escaped, turning the batter into a solid Answer: C Your cookies have coagulated. What has happened? A. They have turned brown B. The sugar has melted and is syrup-lik C. The water has escaped, turning the batter into a solid Answer: C Practice Questions I am making pancakes. I am going to use artificial sugar instead of regular sugar. My pancakes are light and fluffy, but they never turned brown. What happened? A. You work cooking at too low of a temperature B. You did not have sugar which helps it brown C. You used the wrong type of flour D. You didnt put in enough artificial sugar. Answer: B I am making pancakes. I am going to use artificial sugar instead of regular sugar. My pancakes are light and fluffy, but they never turned brown. What happened? A. You work cooking at too low of a temperature B. You did not have sugar which helps it brown C. You used the wrong type of flour D. You didnt put in enough artificial sugar. Answer: B Practice Questions Why does the cake on the right have larger holes than the cake of the left? A. The cooking temperature was too high. B. There was too much salt C. The leavening agent was producing more gas D. All are correct Answer: C Why does the cake on the right have larger holes than the cake of the left? A. The cooking temperature was too high. B. There was too much salt C. The leavening agent was producing more gas D. All are correct Answer: C Practice Questions What chemical processes have happened in this picture? A. FermentationB. Coagulation C. DenaturationD. All of above Answer: B, C What chemical processes have happened in this picture? A. FermentationB. Coagulation C. DenaturationD. All of above Answer: B, C Practice Questions What happened to my yeast bread in this picture? A. It did not have enough flour B. It did not have any fats C. It did not have salt, so it reacted too quickly. D. There was no egg whites. Answer: C What happened to my yeast bread in this picture? A. It did not have enough flour B. It did not have any fats C. It did not have salt, so it reacted too quickly. D. There was no egg whites. Answer: C Practice Questions My cookies turned out terrible. They never turned brown. They are tough and dry. What mistakes did I make? Answer: Not enough sugar Perhaps the heat was too low to brown You overmixed the dough developing too much gluten Answer: All are correct My cookies turned out terrible. They never turned brown. They are tough and dry. What mistakes did I make? Answer: Not enough sugar Perhaps the heat was too low to brown You overmixed the dough developing too much gluten Answer: All are correct Leavening Agents Baking Soda Needs acid to react to produce carbon dioxide Baking Powder Made of baking soda, thickener, and added acids. Single acting reacts when mixed with liquid to produce CO 2 Double acting two acids, reacts with mixed and when heat is added Cream of tartar acid that is added to baking powder Steam produces steam which rises and helps bring up dough or batter Egg whites whipped to incorporate air which helps batter to rise Yeast biological agent that makes carbon dioxide when fed sugar, needs warm temperatures Baking Soda Needs acid to react to produce carbon dioxide Baking Powder Made of baking soda, thickener, and added acids. Single acting reacts when mixed with liquid to produce CO 2 Double acting two acids, reacts with mixed and when heat is added Cream of tartar acid that is added to baking powder Steam produces steam which rises and helps bring up dough or batter Egg whites whipped to incorporate air which helps batter to rise Yeast biological agent that makes carbon dioxide when fed sugar, needs warm temperatures Practice Question I am making pancakes with baking soda and regular milk. They do not get light and fluffy. What was missing? A. Leavening AgentB. Acid C. EggsD. Flour Answer: B I am making pancakes with baking soda and regular milk. They do not get light and fluffy. What was missing? A. Leavening AgentB. Acid C. EggsD. Flour Answer: B Practice Question Which of the following are acids added to baking powder? A. Cream of tartar B. Lemon juice C. All Purpose flour D. Vinegar Answer: A Which of the following are acids added to baking powder? A. Cream of tartar B. Lemon juice C. All Purpose flour D. Vinegar Answer: A Practice Question I am making yeast bread. My bread does not rise. What might have been the problem? A. You may not have added sugar B. You may have not mixed it enough C. You may have used cold liquids D. All of the above Answer D I am making yeast bread. My bread does not rise. What might have been the problem? A. You may not have added sugar B. You may have not mixed it enough C. You may have used cold liquids D. All of the above Answer D Practice Questions My muffins turned out tough and too chewy. I used all purpose flour. What did I do wrong? Answer: You might have overstirred, developing gluten too much My muffins turned out tough and too chewy. I used all purpose flour. What did I do wrong? Answer: You might have overstirred, developing gluten too much Practice Questions Which flour would be more suitable for making cinnamon rolls? A. Cake flour B. All purpose flour C. Bread flour Answer: B want it to be more tender Which flour would be more suitable for making cinnamon rolls? A. Cake flour B. All purpose flour C. Bread flour Answer: B want it to be more tender Biochemicals Carbohydrates: Building block monosaccharides Elements: Carbon, Hydrogen, Oxygen Functions: provide energy Foods: Fruits, Vegetables, Sweet products such as cake, cookies, etc Carbohydrates: Building block monosaccharides Elements: Carbon, Hydrogen, Oxygen Functions: provide energy Foods: Fruits, Vegetables, Sweet products such as cake, cookies, etc Biochemicals Lipids: Building blocks: Glycerol and Fatty Acids Elements: Carbon, Hydrogen, Oxygen Functions: Long-term energy storage, make up the cell membranes (phospholipids), hormones Foods: Fats and Oils, Cholesterol, Waxes Fats saturated (solid) Oils unsaturated (liquid) Lipids: Building blocks: Glycerol and Fatty Acids Elements: Carbon, Hydrogen, Oxygen Functions: Long-term energy storage, make up the cell membranes (phospholipids), hormones Foods: Fats and Oils, Cholesterol, Waxes Fats saturated (solid) Oils unsaturated (liquid) Biochemicals Proteins: Building Block: Amino Acids (20) Elements: Carbon, hydrogen, oxygen, nitrogen, sometimes sulfur Functions: enzymes, cell membrane, provide structure, building materials, hormones Foods: Meats, Eggs, Nuts, Legumes (beans and peas), Dairy products Proteins: Building Block: Amino Acids (20) Elements: Carbon, hydrogen, oxygen, nitrogen, sometimes sulfur Functions: enzymes, cell membrane, provide structure, building materials, hormones Foods: Meats, Eggs, Nuts, Legumes (beans and peas), Dairy products Biochemicals Nucleic Acids Building Blocks: Nucleotides Functions: Genetic makeup (DNA), protein synthesis (RNA) Foods: All food from living things Nucleic Acids Building Blocks: Nucleotides Functions: Genetic makeup (DNA), protein synthesis (RNA) Foods: All food from living things Other nutrients: Vitamins organic molecules helps with chemical reactions in body, growth and metabolism Minerals inorganic molecules that also help with chemical reactions, building materials Water activates chemical reactions, helps transport nutrients through blood Organic contains Carbon Inorganic does not contain Carbon Vitamins organic molecules helps with chemical reactions in body, growth and metabolism Minerals inorganic molecules that also help with chemical reactions, building materials Water activates chemical reactions, helps transport nutrients through blood Organic contains Carbon Inorganic does not contain Carbon Practice Questions: Which is the primary biomolecule that is found in eggs? Answer: Protein Which is the primary biomolecule that is found in eggs? Answer: Protein Practice Questions What would fruits be classified as: A. CarbohydratesB. Lipids C. Proteins Answer: Carbohydrates What would fruits be classified as: A. CarbohydratesB. Lipids C. Proteins Answer: Carbohydrates Practice Questions What would DNA be classified as: A. CarbohydratesB. Lipids C. ProteinsD. Nucleic Acids Answer: Nucleic Acids What would DNA be classified as: A. CarbohydratesB. Lipids C. ProteinsD. Nucleic Acids Answer: Nucleic Acids Practice Questions What are these food items classified as: A. CarbohydratesB. Lipids C. Proteins Answer: Lipids What are these food items classified as: A. CarbohydratesB. Lipids C. Proteins Answer: Lipids Practice Questions What are these food items classified as: A. CarbohydratesB. Lipids C. Proteins Answer: Proteins What are these food items classified as: A. CarbohydratesB. Lipids C. Proteins Answer: Proteins Practice Questions What 2 biochemicals have the same elements? A. CarbohydratesB. Lipids C. ProteinsD. Nucleic Acids Answer: A and B What 2 biochemicals have the same elements? A. CarbohydratesB. Lipids C. ProteinsD. Nucleic Acids Answer: A and B Practice Questions What biochemicals are in your cell membranes? A. ProteinB. Carbohydrates C. Lipids Answer: A and C What biochemicals are in your cell membranes? A. ProteinB. Carbohydrates C. Lipids Answer: A and C Practice Questions What biochemical gives you instant energy? A. ProteinB. Carbohydrates C. Lipids Answer: B What biochemical gives you instant energy? A. ProteinB. Carbohydrates C. Lipids Answer: B Acids and Bases Acids: Sour Taste, release H+ ions when dissolved in water, pH 0 6.99 Bases: Bitter Taste, release OH-, pH to 14 Closer an acid or base is to 7, weaker Further away from 7, stronger 7 is neutral Acids: Sour Taste, release H+ ions when dissolved in water, pH 0 6.99 Bases: Bitter Taste, release OH-, pH to 14 Closer an acid or base is to 7, weaker Further away from 7, stronger 7 is neutral Acids and Bases Body uses acids in digestive system, makeup of many vitamins Body uses bases to help neutralize acids Kidney and lungs help get rid of excess acids and bases Kidneys produce bicarbonates (bases) Lungs carry out acids with exhaling of carbon dioxide Bloods pH should be 7.4 Body uses acids in digestive system, makeup of many vitamins Body uses bases to help neutralize acids Kidney and lungs help get rid of excess acids and bases Kidneys produce bicarbonates (bases) Lungs carry out acids with exhaling of carbon dioxide Bloods pH should be 7.4 Practice Questions What object is a stronger acids? A.Soda B.Milk C.Apple D.Shampoo Answer: A What object is a stronger acids? A.Soda B.Milk C.Apple D.Shampoo Answer: A Practice Questions What object is a stronger Base? A.pH of 14 B.pH of 2 C.pH of 7 D.pH of 8 Answer: A What object is a stronger Base? A.pH of 14 B.pH of 2 C.pH of 7 D.pH of 8 Answer: A Practice Questions What object is an acid? A.pH of 14 B.pH of 2 C.pH of 7 D.pH of 8 Answer: A What object is an acid? A.pH of 14 B.pH of 2 C.pH of 7 D.pH of 8 Answer: A Practice Questions What is another name for alkalines: A.AcidsB. BasesC. Neutral compounds Answer: B What is another name for alkalines: A.AcidsB. BasesC. Neutral compounds Answer: B Practice Questions What is blood? A.AcidB. BaseC. Neutral Answer: B (7.4 pH) What is blood? A.AcidB. BaseC. Neutral Answer: B (7.4 pH) Practice Questions Of the pictured items, which is a stronger acid? Answer: Vinegar Of the pictured items, which is a stronger acid? Answer: Vinegar