Definitions and pH
What does pH measure?
How acidic or basic a substance is.
What taste is commonly associated with acids?
Sour.
What colour does blue litmus show in an acid?
Red.
When an acid reacts with a base two products are made. These are a salt and ________.
Water.
Which pH value is considered neutral?
pH of 7.
What feeling is commonly associated with bases?
Soapy / Slippery
What is a common tool for measuring acidity of a solution?
pH paper / pH meter / Universal indicator
What is the name of the salt formed when sodium hydroxide reacts with hydrochloric acid?
Sodium Chloride.
Which is more acidic: pH = 2 or pH = 5?
pH = 2
What word is used to describe an acid or base being able to "eat away" at substances?
Corrosive.
What colour will universal indicator show for a strong base?
Dark blue / Purple.
When an acid reacts with a carbonate, fizzing is observed. How can we check that this gas is carbon dioxide?
Bubble the gas through limewater. The limewater will turn cloudy if the gas is carbon dioxide.
What is the range of pH values for basic substances?
8 - 14.
When a piece of magnesium was dropped into a solution, it fizzed. Is the solution acidic or basic?
Acidic.
What colour would blue litmus paper show in a neutral solution?
Blue.
When an acid reacts with a metal. Fizzing is observed. What gas is responsible for this fizzing?
Hydrogen gas.
Give a definition for the term Neutralisation.
Neutralisation is the reaction that occurs when an acid reacts with a base to create water and a salt.
What element is present in the formula of every acid?
Hydrogen (H)
Why is using universal indicator often more useful than using litmus paper?
It shows the approximate pH value, not just if it is acidic or basic.
Name two reactants (1 acid and 1 base) that could be used to make the salt Copper Nitrate
Copper hydroxide + Nitric acid
Copper carbonate + Nitric acid