Deduce the numbers of electrons, neutrons and protons in one atom of the sodium isotope shown. $^{23}_{11}\text{Na}$
State the colour displayed by chlorine gas.
Chlorine is a diatomic molecule. State what the word diatomic means.
Complete the chemical equation for sodium reacting with chlorine. $2\text{Na} + \dots \rightarrow \dots \text{NaCl}$
Sodium chloride is an ionic compound. Describe two physical properties that ionic compounds have.
Complete the table by estimating the melting point of potassium and the atomic radius of sodium.
Predict the physical state of rubidium at 700 ^{\circ}C. Give a reason for your answer.
Give two physical properties of Group I metals that are different from transition elements and state the difference.
Aqueous chlorine reacts with aqueous sodium iodide. $\text{Cl}_2 + 2\text{NaI} \rightarrow 2\text{NaCl} + \text{I}_2$ Explain how this equation shows that chlorine is more reactive than iodine.