Go to the Quizzes Page Balancing Chemical Equations 0% 66 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 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. Less than 5 grams. Impossible to determine without knowing the amount of oxygen used. 2 / 20 What are the missing coefficients for the chemical equation below? P + O2 → P2O5 1 , 3 , 4 4 , 5 , 2 2 , 5 , 4 2 , 2 , 5 3 / 20 When balancing the equation Fe + S → FeS, what coefficient is needed in front of FeS? 2 3 It cannot be balanced. 1 4 / 20 In the balanced equation 2H₂ + O₂ → 2H₂O, what is the coefficient of hydrogen (H) on the product side? 2 4 3 1 5 / 20 When balancing an equation, you can change the subscripts in the chemical formulas. True False 6 / 20 A chemical reaction happens when ___________. existing atoms in the reactants are destroyed existing bonds break and the atoms rearrange to form new bonds new atoms are created in the products new bonds are formed to create complex compounds 7 / 20 What is the Law of Conservation of Mass? Energy can be neither created nor destroyed. The total energy absorbed and released from a chemical reaction varies. Matter can be neither created nor destroyed in a chemical reaction. The total charge of a system must remain constant. 8 / 20 What are the missing coefficients for the chemical equation below? Ag2O → Ag + O2 5 , 4 , 2 1 , 2 , 3 2 , 2 , 2 2 , 4 , 1 9 / 20 What does balancing a chemical equation mean? Adding heat to a reaction Changing the names of the reactants and products Making sure the number of atoms of each element is the same on both sides of the reaction arrow Replacing elements with different ones 10 / 20 Why is it important to balance a chemical equation? To represent the Law of Conservation of Mass To make the equation look neat To identify the reactants and products To calculate the rate of reaction 11 / 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 large number written in front of a chemical formula A small number written behind a chemical formula 12 / 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. Equal to the total mass of the products. Unrelated to the total mass of the products. Less than the total mass of the products. 13 / 20 In the balanced equation N₂ + 3H₂ → 2NH₃, how many atoms of hydrogen (H) are on the reactant side? 2 6 4 3 14 / 20 In the unbalanced equation: Fe + O2 → FeO3 how many Fe atoms are on the reactant side? 2 1 It depends on the amount of Fe used There is no Fe in the equation 15 / 20 Which of the following equations is balanced? 2Na + 2Cl2 → 2NaCl Fe + 2HCl → FeCl2 + H C3H8 + 5O2 → 3CO2 + 4H2O H2 + O2 → H2O 16 / 20 When balancing an equation, you can: Change the chemical formulas of the reactants and products Change the coefficients in front of the formulas Add or remove atoms from the equation None of the above 17 / 20 Which statement best describes the law of conservation of energy? 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 stays the same. Energy can't be transferred between the system and the surroundings. The total energy absorbed and released from a chemical reaction varies. 18 / 20 What is the coefficient needed in front of O2 to balance the following equation? CH4 + O2 → CO2 + 2H2O 2 4 3 1 19 / 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 + 2H2O CH4 + 2O2 → CO2 + 2H2O CH4 + 2O2 → 2CO2 + H2O CH4 + O2 → CO2 + H2O 20 / 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 Your score is 0% Restart quiz Go to the Quizzes Page