In the year 2016, a mishap took place near Mahad in the Raigad district of Maharashtra. The 106 years old British-era bridge over the Savitri River collapsed into the river. Two buses carrying 22 people went missing after being swept away by the river. Navy divers, helicopter of Coast Guard began the rescue operation of the affected area. A 300 kg magnet was lowered into the swollen Savitri River by the rescue team. Why do you think the huge magnet was lowered into the river?

 to locate and possibly retrieve the buses

Explanation:

The buses are presumed to be made of steel. Presumably, a bus and the magnet are mutually attractive. The magnet could be used to locate a missing bus, and possibly retrieve it.

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e