Chemical Reactions and Ions

What does the symbol 'C' represent in chemistry?

• Chlorine

• Calcium

• Carbon

• Copper

How many copper atoms are represented by the notation '2CU'?

• Four

• Three

• Two

• One

What does the formula 'H2O' represent?

• One molecule of hydrogen

• Two molecules of oxygen

• One molecule of water

• Two molecules of hydrogen

In a chemical equation, what does the arrow typically represent?

• The balance of the equation

• The direction of the reaction

• The start of a reaction

• The end of a reaction

What is an ion?

• A stable molecule

• A molecule with no charge

• An atom with a net electric charge

• A neutral atom

Which of the following is a negatively charged ion?

• Chloride ion

• Iron ion

• Lead ion

• Sodium ion

What is a cation?

• A negatively charged ion

• A positively charged ion

• A neutral molecule

• An unstable ion

What is a free radical?

• A stable molecule

• A molecule with paired electrons

• A molecule with unpaired electrons

• A charged ion

Which of the following is an example of a reactive oxygen species?

• Lead ion

• Hydrogen peroxide

• Sodium ion

• Chloride ion

How is a hydroxy radical formed?

• By the addition of electrons

• By the reduction of an oxygen molecule

• By the oxidation of hydrogen

• By the combination of sodium and chloride