An anhydrous white salt, Z, is heated strongly for 30 minutes. A mixture of gases is given off. The solid remaining in the test-tube is then dissolved in a small volume of dilute hydrochloric acid. The addition of a few drops of dilute sulfuric acid to the test-tube causes a white precipitate to form. Which substance could be Z?

Separate samples of magnesium and calcium are added to an excess of dilute sulfuric acid. The observations are summar…

Dolomite is a double carbonate, CaMg(CO₃)₂, and can be used instead of calcium carbonate for treating acidic soils. T…

A reaction scheme for a Group 2 metal, M, is shown. M --(reacts with oxygen)--> X --(reacts with water)--> Y --(react…

The eight species that follow all have covalent bonds. In which pair do the species have different shapes from each o…

A sample of gas occupies 240 cm³ at 37 °C and 100 kPa. How many moles of gas are present in the sample?

The standard enthalpy changes of combustion of carbon, hydrogen and methanol are shown. C(s) + O₂(g) → CO₂(g) ∆Hᶜ = −…