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