Metals like sodium, potassium, calcium and magnesium are extracted by electrolysis of their chlorides in a molten state. These metals are not extracted by reduction of their oxides with carbon because: (i) Reduction with carbon is very expensive. (ii) Carbon readily makes alloys with these metals. (iii) Carbon has less affinity for oxygen. (iv) Carbon is a weaker reducing agent than these metals.

A 0.4560 g mixture of FeCl3 and FeBr3 was dissolved in water and reacted with excess NaOH. All of the iron precipitated as Fe(OH)3. The mass of the Fe(OH)3 produced was 0.1832 g. Calculated the % w/w composition of the FeCl3 in the original mixture.

Consider the solutions presented: (a) Which of the following sketches best represents the ions in a solution of Fe(NO3)3(aq)? (b) Write a balanced chemical equation showing the products of the dissolution of Fe(NO3)3.

Tetraphosphorus decaoxide (P₄O₁₀) is made from phos-phate rock and used as a drying agent in the laboratory.(a) Write a balanced equation for its reaction with water.(b) What is the pH of a solution formed from the addition of 8.5 g of P₄O₁₀ in sufficient water to form 0.750 L?