Magnesium is a shiny, flexible metal that can be burned in the presence of air. When it is burned, it produces a white powder that is no longer shiny or flexible.
This white powder also has more mass than the original magnesium. *
The molecules were separated into individual atoms.
The mass of the magnesium changed.
Smoke that was trapped between the magnesium atoms was given off.
A new substance wa formed
Explain why you chose the above answer. *
Your answer

A new substance was formed

Explanation:

According to this question, a shiny and flexible metal called Magnesium (Mg) is burnt in air to produce a white powder that has no shiny or flexible properties, however, has more weight than the magnesium metal itself.

This is possible because a CHEMICAL CHANGE has occured, hence, a new substance has been formed. The formation of a new substance during the burning process (chemical reaction), induced the increase in mass.

d.7.5cm is your answer

0.19 m/s and 0.45 m/s