acids and alkalies

• what is the ph of a neutral solution?


   A neutral solution has a pH value of 7.
• The pH scale is a measurement system used to indicate how acidic or alkaline (basic) a substance is. It ranges from 0 to 14:

  • A pH less than 7 indicates an acidic solution (e.g., lemon juice).

  • A pH of 7 is neutral (e.g., pure water).

  • A pH greater than 7 indicates an alkaline (basic) solution (e.g., baking soda solution).

  
• how would you measure the ph of a solution using the ph scale?


  To measure the pH of a solution, you can use a universal indicator or a pH meter. The universal indicator can be either paper or a liquid solution, which changes color when added to the solution. You then compare the color to a pH chart to find the pH. A pH meter, on the other hand, is a device with a probe that gives an accurate pH reading when placed in the solution.
• what is more accurate, a ph meter or a ph scale? explain why


  a ph meter as the ph scale is down to opinion. for example, somebody may consider a specific shade of red to be a ph of 3 whereas somebody else may think it has a ph of 2.
• Universal indicator is one example of an acid-alkali indicator. Indicators show whether a solution is acidic, neutral (pH 7) or alkaline. The table shows the colours for litmus paper.

  
• metal oxides and metal hydroxides are bases, true or false?


  true
• reaction for when acids react with metals 


  Acid + metal → salt + hydrogen
• Name the two products of the reaction of zinc with hydrochloric acid.


  The products are zinc chloride and hydrogen.
• Predict the name of the salt formed when copper oxide reacts with nitric acid.


  The salt formed is copper nitrate.
• Reactions with carbonates


  A salt, water and carbon dioxide are produced when acids react with carbonates. In general:

  Acid + carbonate → salt + water + carbon dioxide
• Reactions with bases, including alkalis

  Metal oxides are bases. In general, when an acid reacts with a metal oxide, the products are a salt and water.

  Acid + metal oxide or base → salt + water
• what does the symbol ⇌ mean?


  The ⇌ symbol is used in the equation to show that the reaction is a reversible reaction and does not go to completion.
• What is the name of the salt formed when hydrochloric acid reacts with sodium hydroxide?


  When hydrochloric acid reacts with sodium hydroxide, the salt produced is sodium chloride (table salt), and water is formed.
• what is a weak acid in terms of ionisation?


  A weak acid is an acid that partially ionises in water.
• what is a strong acid in terms of ionisation?

  A strong acid is an acid that completely ionises in water. 
• what is a reaction between an acid and alkaline called?

  nutrelisation reaction
• Acids and alkalis are substances that produce ions in aqueous solution. what ions do they form?

  •Acids produce H⁺ (hydrogen) ions in aqueous solution.

  •Alkalis (soluble bases) produce OH⁻ (hydroxide) ions in aqueous solution.
• what is the PH of a strong acid

  PH 1-3
• Ethanoic acid is a weak acid. What is meant by ‘weak acid’?

  (the acid is only) partially ionised (in aqueous solution)
• Give the formula of the ion that makes a solution alkaline.

  OH− 
• strong acid


  completely ionizes in aqueous solution. for example HCL will split into all ions like h+ and cl-
• what are ions?


  • Ions are charged particles formed when atoms gain or lose electrons.

  • If an atom loses an electron, it becomes a positively charged ion (cation).

  • If an atom gains an electron, it becomes a negatively charged ion (anion).
• list many positive ions (cations)

  • Hydrogen (H) → H⁺

  • Lithium (Li) → Li⁺

  • Sodium (Na) → Na⁺

  • Potassium (K) → K⁺

  • Calcium (Ca) → Ca²⁺

  • Magnesium (Mg) → Mg²⁺

  • Aluminum (Al) → Al³⁺

  • Iron (Fe) → Fe²⁺ (Iron(II))

  • Iron (Fe) → Fe³⁺ (Iron(III))

  • Zinc (Zn) → Zn²⁺

  • Copper (Cu) → Cu²⁺

  • Silver (Ag) → Ag⁺

  • Lead (Pb) → Pb²⁺
• list many negative ions (anions)

  • Chlorine (Cl) → Cl⁻

  • Oxygen (O) → O²⁻

  • Sulfur (S) → S²⁻

  • Nitrogen (N) → N³⁻

  • Hydroxide (OH) → OH⁻

  • Carbonate (CO₃²⁻) → CO₃²⁻

  • Nitrate (NO₃⁻) → NO₃⁻

  • Sulfate (SO₄²⁻) → SO₄²⁻

  • Phosphate (PO₄³⁻) → PO₄³⁻