This question is about elements, compounds, and mixtures.
Which type of substance is sulfur dioxide?
The diagrams in Figure 1 represent different substances using circle models.
◯\bigcirc◯ and ∙\bullet∙ represent atoms of two different elements.

Which diagram in Figure 1 represents a pure compound?
Which diagram in Figure 1 represents a mixture of two elements?
State the method used to separate a mixture of different coloured pigments in a water-soluble dye.
A mixture containing three liquids with boiling points of 56∘C56^\circ\text{C}56∘C, 110∘C110^\circ\text{C}110∘C, and 138∘C138^\circ\text{C}138∘C is separated by fractional distillation. Which liquid distils and is collected last?