Classify each of the following as (a) solid, (b) liquid, (c) gas, (d) element, (e) compound, and/or (f) mixture.
i) Ice
ii) Soda
iii) Iron
iv) Heliox

• A. i) Ice: (a) solid, (d) element
  ii) Soda: (c) gas, (f) mixture
  iii) Iron: (a) solid, (d) element
  iv) Heliox: (c) gas, (e) compound
• B. i) Ice: (a) solid, (e) compound
  ii) Soda: (b) liquid, (f) mixture
  iii) Iron: (a) solid, (d) element
  iv) Heliox: (c) gas, (f) mixture
• C. i) Ice: (b) liquid, (d) element
  ii) Soda: (b) liquid, (f) mixture
  iii) Iron: (a) solid, (e) compound
  iv) Heliox: (b) liquid, (d) element
• D. i) Ice: (c) gas, (f) mixture
  ii) Soda: (a) solid, (e) compound
  iii) Iron: (a) solid, (f) mixture
  iv) Heliox: (a) solid, (d) element

Answer: (B)