Question 35
A teacher provides three equal 3-cm pieces of magnesium ribbon: A is a straight strip, B is cut into small pieces, and C is folded in layers. Wearing goggles and gloves, put 25 cm³ of dilute sulfuric acid into each labelled conical flask. Add the corresponding magnesium sample and start a stopwatch immediately. Record the time for the magnesium to disappear completely. Work under teacher supervision, away from flames; hydrogen gas is produced.
Identify the variable that is changed.
Identify the variable that is changed.
