It increases the yield of the product.
It increases the speed of the reactant particles.
It increases the activation energy of the reaction.
It provides an alternative pathway for the reaction to occur.
The concentration of the sulfuric acid
The pressure at which the reaction takes place
The size of the particles of copper(II) oxide
The temperature of the reacting mixture
40 g of HCl in 1000 cm3 of water.
20 g of HCl in 1000 cm3 of water.
15 g of HCl in 500 cm3 of water.
10 g of HCl in 100 cm3 of water.
An insoluble layer of calcium chloride is formed on the calcium carbonate.
The pieces of calcium carbonate gradually become smaller.
The calcium carbonate is covered by bubbles of carbon dioxide.
The concentration of hydrochloric acid gradually reduces to zero.
Marble chips and dilute acid at 40 degrees celsius.
Marble chips and concentrated acid at 20 degrees celsius.
Marble powder and dilute acid at 20 degrees celsius.
Marble powder and concentrated acid at 40 degrees celsius.
A black solid and a colourless liquid
A black solid and a blue liquid
A blue liquid only
A light blue solid and a colourless liquid
The amount of magnesium is decreasing
The magnesium is acting as a catalyst
The solution is becoming hotter
The surface area of the magnesium is increasing
It increases the yield of the products.
It makes the reaction more exothermic (heat releasing).
It lowers the activation energy of the reaction.
It prevents a reverse reaction from occurring.
The synthesis of ammonia
The fermentation of sugar
The oxidation of sulfur dioxide
The electrolysis of sodium chloride
Pieces of solid - larger; acid - less concentrated; temperature - lower
Pieces of solid - larger; acid - more concentrated; temperature - higher
Pieces of solid - smaller; acid - less concentrated; temperature - lower
Pieces of solid - smaller; acid - more concentrated; temperature - higher