Which negative ion has the lowest concentration?
State the name of the compound formed only from $\text{K}^+$ and $\text{Br}^-$ ions.
Calculate the mass of calcium ions in a $250\,\text{cm}^3$ sample of this water.
Complete the equation to show how a fluoride ion is formed from a fluorine atom. $\text{F} + \ldots \rightarrow \text{F}^-$
Describe how to test for sulfate ions. test observations
What does the term sublimation mean?
Complete the chemical equation for this reaction. $\text{S} + \ldots\,\text{H}_2\text{SO}_4 \rightarrow \text{2H}_2\text{O} + \ldots\,\text{SO}_2$
Use the data in the table to suggest a method for obtaining pure, dry samples of both sulfur and zinc from a mixture of sulfur powder and zinc powder.
Deduce the molecular formula of this compound from the numbers of sulfur, fluorine and oxygen atoms.