(a) Magnesium reacts with oxygen to form magnesium oxide. State two observations that would be made when magnesium is heated strongly and placed in a gas jar of pure oxygen. [1] (b) Acid indigestion is caused by an excess of hydrochloric acid in the stomach. Magnesium oxide is commonly found in indigestion tablets. (i) Give the equation to show how magnesium oxide relieves acid indigestion. [1] (ii) Name the type of reaction that occurs in (b)(i). [1] (c) Magnesium oxide is described as a ceramic material. It has a high melting point. State and explain why ceramic materials such as magnesium oxide have high melting points. [2] (d) Magnesium oxide can be made from magnesium carbonate in a one-step reaction using heat. (i) Write an equation for this reaction. Include state symbols. [1] (ii) Name the type of reaction occurring during this process. [1] [Total: 7]