Go to the Quizzes Page Balancing Chemical Equations 0% 15 Created by AbuBakrShalabi Click "Watch Now" to watch the video. Then, answer the following questions: Please write your name and email to receive your certificate. 1 / 20 In the balanced equation 2H₂ + O₂ → 2H₂O, what is the coefficient of hydrogen (H) on the product side? 4 3 2 1 2 / 20 What are the missing coefficients for the chemical equation below? Ag2O → Ag + O2 2 , 4 , 1 5 , 4 , 2 2 , 2 , 2 1 , 2 , 3 3 / 20 What is the Law of Conservation of Mass? The total charge of a system must remain constant. The total energy absorbed and released from a chemical reaction varies. Matter can be neither created nor destroyed in a chemical reaction. Energy can be neither created nor destroyed. 4 / 20 Which of the following equations is balanced? Fe + 2HCl → FeCl2 + H H2 + O2 → H2O 2Na + 2Cl2 → 2NaCl C3H8 + 5O2 → 3CO2 + 4H2O 5 / 20 When balancing an equation, you can change the subscripts in the chemical formulas. False True 6 / 20 What does balancing a chemical equation mean? Changing the names of the reactants and products Replacing elements with different ones Making sure the number of atoms of each element is the same on both sides of the reaction arrow Adding heat to a reaction 7 / 20 In a closed system undergoing a chemical reaction, the total mass of the reactants must be: Unrelated to the total mass of the products. Less than the total mass of the products. Greater than the total mass of the products. Equal to the total mass of the products. 8 / 20 In a balanced equation, the total number of atoms of each element must be the same on both sides of the reaction arrow. True False 9 / 20 Why is it important to balance a chemical equation? To calculate the rate of reaction To identify the reactants and products To make the equation look neat To represent the Law of Conservation of Mass 10 / 20 In the unbalanced equation: Fe + O2 → FeO3 how many Fe atoms are on the reactant side? 2 It depends on the amount of Fe used 1 There is no Fe in the equation 11 / 20 In the balanced equation N₂ + 3H₂ → 2NH₃, how many atoms of hydrogen (H) are on the reactant side? 3 2 6 4 12 / 20 What is the balanced equation for the reaction between methane (CH4) and oxygen (O2) to produce carbon dioxide (CO2) and water (H2O)? CH4 + O2 → CO2 + H2O CH4 + 2O2 → CO2 + 2H2O CH4 + 2O2 → 2CO2 + H2O CH4 + O2 → CO2 + 2H2O 13 / 20 What are the missing coefficients for the chemical equation below? P + O2 → P2O5 2 , 5 , 4 2 , 2 , 5 4 , 5 , 2 1 , 3 , 4 14 / 20 If 5 grams of magnesium (Mg) react with oxygen (O₂) to form magnesium oxide (MgO), the total mass of the magnesium oxide produced will be: More than 5 grams. Exactly 5 grams. Impossible to determine without knowing the amount of oxygen used. Less than 5 grams. 15 / 20 A chemical reaction happens when ___________. new atoms are created in the products existing bonds break and the atoms rearrange to form new bonds new bonds are formed to create complex compounds existing atoms in the reactants are destroyed 16 / 20 What is the coefficient in a balanced chemical equation? A small number written behind a chemical formula An element on the left side of the equation A large number written in front of a chemical formula An element on the right side of the equation 17 / 20 When balancing the equation Fe + S → FeS, what coefficient is needed in front of FeS? 2 1 3 It cannot be balanced. 18 / 20 What is the coefficient needed in front of O2 to balance the following equation? CH4 + O2 → CO2 + 2H2O 2 3 4 1 19 / 20 Which statement best describes the law of conservation of energy? The total energy absorbed and released from a chemical reaction stays the same. The total energy absorbed and released from a chemical reaction varies. Energy can't be transferred between the system and the surroundings. The amount of energy released by a system must be more than that absorbed by the surrounding. 20 / 20 When balancing an equation, you can: Change the coefficients in front of the formulas Add or remove atoms from the equation Change the chemical formulas of the reactants and products None of the above Your score is 0% Restart quiz Go to the Quizzes Page