1) Substance A is a grey solid that consists of an Alkaline earth metal and carbon (37.5% by mass). It reacts with Substance B to produce Substances C & D. Forty million trillion formula units of A have a mass of 4.26 milligrams.

2) 47.9 grams of Substance B contains 5.36 grams of hydrogen and 42.5 grams of oxygen.

3) When 10. grams of C is burned in excess oxygen, 33.8 grams of Carbon Dioxide and 6.92 grams of water are produced. A mass spectrum of Substance C shows a parent molecular ion with a mass-to-charge ration of 26.

4) Substance D is the hydroxide of the metal in substance A.