Matter and Chemical Change at Home and Work

Classifying and balancing the everyday reactions of Science 24: composition, decomposition, combustion and neutralization.

13 questions, free, marked as you go with a worked explanation on every one.

What this covers

A propane barbecue burns fuel according to C₃H₈ + 5O₂ → 3CO₂ + 4H₂O. Which type of reaction is this?
Balance the equation for the formation of water by counting atoms: __H₂ + O₂ → __H₂O. What coefficient goes in front of H₂O?
Hydrogen peroxide slowly breaks down in the bottle: 2H₂O₂ → 2H₂O + O₂. Which type of reaction is this?
An antacid tablet is taken to relieve excess stomach acid. The reaction between the antacid and the acid produces a salt and water. Which type of reaction is this?
A solution with a pH of 3 is how many times more acidic than a solution with a pH of 5?
In a sealed container, 8.0 g of magnesium combines with 5.3 g of oxygen to form magnesium oxide, and both reactants are used up completely. What mass of magnesium oxide forms, in grams?
A WHMIS label on a workplace container shows a flame symbol. What does this tell a worker?
A cleaning solution is made by mixing 250 mL of concentrate with water to make a total volume of 2 000 mL. What percent of the final solution is concentrate?
Use the table. Which reaction type is NaOH + HCl -> NaCl + H2O?
Balance the equation by counting atoms: __C + __O₂ → __CO₂. What coefficient goes in front of C?
Balance the equation: Na + Cl2 -> NaCl. What coefficient belongs in front of NaCl?
Balance the equation: CH4 + O2 -> CO2 + H2O. What coefficient belongs in front of O2?
Balance the equation: CaCO3 -> CaO + CO2. What coefficient belongs in front of CaCO3?