Chemical Changes Flashcards
(17 cards)
Q: What is the reactivity series?
A: A list of metals arranged in order of their reactivity, from the most reactive (potassium) to the least reactive (platinum).
Q: Which metals are the most reactive in the reactivity series?
A: Potassium, sodium, and calcium are the most reactive metals.
Q: Which metals are the least reactive in the reactivity series?
A: Gold, platinum, and silver are the least reactive metals.
Q: What happens when a metal reacts with an acid?
A: The metal reacts with the acid to form a salt and hydrogen gas.
Q: What is the general equation for a metal reacting with an acid?
A: Metal + Acid → Salt + Hydrogen
Q: What is a displacement reaction?
A: A more reactive metal can displace a less reactive metal from its compound.
Q: How are reactive metals like aluminium extracted?
A: Reactive metals are extracted by electrolysis.
Q: How are less reactive metals like iron extracted?
A: Less reactive metals are extracted through reduction (e.g., blast furnace for iron).
Q: What is the pH scale?
A: The pH scale measures the acidity or alkalinity of a substance, with 7 being neutral.
Q: What does a pH below 7 indicate?
A: A pH below 7 indicates an acid.
Q: What does a pH above 7 indicate?
A: A pH above 7 indicates an alkali.
Q: What is neutralization?
A: Neutralization is the reaction between an acid and an alkali (aqueous) to form a salt and water.
Q: What is the general equation for neutralization?
A: Acid (aq) + Base (aq) → Salt (s) + Water (l)
Q: What is the formula for calculating the concentration of a solution?
A: Concentration (g/dm³) = Mass of solute (g) ÷ Volume of solution (dm³)
Q: What does electrolysis do in aqueous solutions?
A: Electrolysis breaks down compounds into their elements by passing an electric current through them.
Q: What happens at the cathode during electrolysis?
A: At the cathode, metal ions are reduced (gain electrons).
Q: What happens at the anode during electrolysis?
A: At the anode, non-metal ions are oxidized (lose electrons).
