Form 1 Science Quiz

Explanation
Oxygen is the correct answer because it is a highly reactive gas that supports combustion. When a glowing splinter is introduced to oxygen, it reacts with the oxygen molecules, causing the splinter to ignite and produce a flame. Carbon dioxide, nitrogen, and hydrogen do not support combustion in the same way that oxygen does, so they would not cause the splinter to ignite.

Explanation
The most accurate percentage of oxygen is 21%. This is because oxygen makes up approximately 21% of the Earth's atmosphere. It is an essential element for many living organisms and plays a crucial role in various biological and chemical processes.

Explanation
Heat transfer through the rod occurs through conduction. Conduction is the transfer of heat between objects that are in direct contact with each other. In this case, the heat is transferred from one end of the rod to the other end by the collision of particles within the rod. The particles with higher kinetic energy transfer their energy to the particles with lower kinetic energy, causing the heat to move along the rod. Conduction is an efficient mode of heat transfer in solids.

Explanation
The thumbtack will fall through different times because the wax that was holding it in place has been melted. When the wax is solid, it provides a strong hold for the thumbtack, preventing it from falling. However, when the wax is melted, it loses its adhesive properties, causing the thumbtack to no longer be securely held in place. As a result, the thumbtack will fall through at different times depending on when the wax was melted and how long it takes for gravity to overcome any remaining friction or resistance.

Explanation
When Iron combines with Sulphur, the resulting compound is called Iron Sulphide. This compound is formed through a chemical reaction between Iron and Sulphur atoms, where the Iron atoms bond with the Sulphur atoms to create a new substance with its own unique properties. Iron Sulphide is commonly found in nature as the mineral pyrite and is also used in various industrial applications.