What are some examples of acids?

Hint:An acid can be defined as a chemical which releases hydrogen ions in water thereby forming salts by integrating with specific metals. pH scale can be used to measure acidity. On pH scale, the value of 7 is considered to be neutral, whereas, a value from 7 to 0 indicates increasing acidity.

Complete step by step answer:
The properties of acids are stated below:
1) Acids react with the active metals and yield hydrogen gas. An example is shown below:
$Zn(s) + {H_2}S{O_4}(aq) \to ZnS{O_4}(aq) + {H_2}(g)$
2) When an acid reacts with a base, they have the tendency to form a salt. An example is shown below:
$NaOH + HCl \to NaCl + {H_2}O$
3) Acids have the tendency to change the colour of specific acid-base indicators. Most common indicators include litmus paper and phenolphthalein. Example: Blue litmus paper turns into red colour in the presence of an acid, whereas phenolphthalein turns colourless.
4) Acids possess a sour taste. Examples: Lemons containing citric acid, vinegar containing acetic acid
5) Aqueous solutions of acids are considered to be electrolytes, as they conduct an electrical current.
Other examples of acids along-with their uses are also listed in the table given below:


Note: There are certain factors that influence acidity of compounds which are: (i) Electronegativity: Acidity goes on increasing as you move from left to right in a periodic chart. (ii) Anion size: Acidity goes on increasing as you move from top to down in a periodic chart. (iii) Resonance: Anions having resonance structures are more acidic in comparison to anions which don't have.