2.2 Acids, Bases and Salts Flashcards
What does the pH scale measure?
The concentration of hydrogen irons in the substance
What do acids contain?
Hydrogen H+ ions
Lower pH, stronger acid 🟰
High concentration of H+ ions
Lower pH, stronger acid
What do alkalis contain?
Hydroxide ions, OH-
Higher pH, stronger alkali 🟰
Higher concentration of OH- ions
Higher pH, stronger alkali
Strong acids, what numbers in pH scale
Lower numbers
Strong alkali is what numbers in pH scale
Higher numbers
What do acids produce when they dissolve in water?
Hydrogen ions
HCl (aq) ➡️ H+ ➕Cl-
What makes an acid a strong acid
Nearly all of the hydrogen atoms form H+ ions when dissolved in water
Fully dissociate (ionise)
What is a base
Chemically opposite to an acid
What is an alkali
A base that dissolved in water
What do alkalis do when dissolved in water
Produce hydroxide ions OH-
Why is ethanoic acid a weak acid for
Only1% of the H molecules form H+ ions When dissolved in water - partially dissociate/ionise
Why is HCl a strong acid
Nearly all of the hydrogen atoms form H+ ions when dissolved in water
Fully dissociate/ionise
What is a dilute acid
More water molecules mixed with the H+
Concentrated acid
Fewer water molecules mixed with the H+ ions
Strong acids react more quickly or slowly than weak acids
More quickly
What do acids react with to form salts
Metals
Bases
Carbonates
Réaction of acid ➕ metal- products
Example
Acid➕metal➡️salt➕hydrogen
Hydrochloric acid ➕ zinc➡️zinc chloride➕hydrogen
What will you see in a reaction with a more reactive metal
Faster reaction
More bubbling
Bigger temperature rise