Match the names of ions and radicals from 1 to 10 with their correct answer from A to Q.

State which of the following formulas of compounds A to J are incorrect. If incorrect write the correct formula.

Fill in the blanks with the correct word from the words in brackets :

1. A symbol represents a short form of a/an …………… [atom/element/molecule]
2. Compounds are always …………… [heterogeneous/homogeneous] in nature.
3. Variable valency is exhibited, since electrons are lost from an element from the …………… [valence/penultimate] shell.
4. A chemical equation is a shorthand form for a …………… [physical/chemical] change.
5. Relative molecular mass of an element/compound is the number of times one …………… of the substance is heavier than -1⁄12^th the mass of an atom of carbon [C¹²]. [atom/ion/molecule]

With reference to a chemical equation, state which of the statements 1 to 5 pertain to A or B.

A : Information provided by a chemical equation.
B : Limitations of a chemical equation

1. The nature of the individual elements.
2. The speed of the reaction.
3. The state of matter in which the substance is present.
4. The completion of the reaction.
5. The direction of the reaction.