The formation of rust or the iron oxide, is by the chemical reaction between iron and atmospheric oxygen. Hence, it is a chemical change involving the formation of new product.
A chemical change is accompanied by the making or breaking or chemical bonds and the formation of new products. Whereas, a physical change does not involve the change in chemical bond. Phase transitions, change in size,shape etc. are physical changes.
The rust formed in the iron material is iron oxide or Fe₂O₃. This process of forming rust by the action of air or water is called corrosion. Iron reacts with atmospheric oxygen or oxygen from water forms the rust.
The formation of rust makes the material destroy and to prevent this process some anticorrosive materials have to be applied. Hence, formation of rust is a chemical change.
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It was one of the earliest times the concept of crustal motion had been presented to the scientific world, and it lay the foundation for the creation of current plate tectonics, even if Wegener's "continental drift" hypothesis was eventually refuted.
In order to comprehend mountain-building processes, volcanic eruptions, earthquakes, the evolution of the Earth's surface, and rebuild the continents and oceans that once covered it, plate tectonics, a theory about the dynamics of the lithosphere, revolutionized Earth sciences.
In the 1960s, the theory of tectonics was developed. The lithosphere, which really is typically 100 km thick and sits on top of the asthenosphere, a plastic layer, is said to be Earth's outermost, unyielding layer.
The lithosphere is divided into several small plates, six to eight medium-sized local plates, and seven extremely massive continental and oceanic plates.
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the minimum amount of horizontal force that the man will need to apply so
that the tree will start moving?
A. 240 N
B. 360 N
C. 480 N
D. 120 N
Answer:
120 N
Explanation: First we shoud consider the forces acted on a tree
Friction foce - acting opposite to the moving direction
Weight - Directly acting downwards
Reaction - Directly acting on upwards
For minimum required force should be equal to the friction force
F = μ R
F = 0.5×480
= 120N
Answer:
Large swarms of locusts can completely strip the foliage and stems of plants such as forbs and grasses. ... They often eat dry plant matter on the ground and will forage for weak or dead grasshoppers when plant food is scarce. As nymphs have a large appetite, they cause more damage than adults.
Explanation:
Answer:
they say yum yum as they eat planets and make humans starve
Explanation:
but they still eat them