Answer with Explanation:
A "chemical change" occurs when the structure of the molecules change. If there's no change in structure, it is called a "physical change." This also means that a <em>chemical reaction </em>has to occur for something to be considered a chemical change.
Gasoline when used as a fuel is being transformed into other forms of energy. It undergoes a process called <em>"combustion."</em>
When used as a fuel for cars, <em>the gasoline is being burned to produce </em><u><em>heat energy.</em></u> This energy is then converted into <u><em>mechanical energy</em></u> that allows the car to move. Clearly, the gasoline has undergone a chemical change.
The correct answer is option 4. In a double covalent bond, two pairs of electrons are bonded or there is a total of four electrons being shared in a bond. For example, we have oxygen. Two atoms of oxygen share two pairs of electrons to have a stable structure.
Answer:
47911.1 pa
Explanation:
The SI base unit of pressure is pascal, which is N/m^2.
2200 kg is 2200*9.8=21560 N, and 4500 cm^2=4500/10000=0.45 m^2.
So the total pressure exerted on the ground (!!) is 21560/0.45= 47911.1 Pa.
Answer:
The correct option is;
C. Old Age River
Explanation:
Among the three stages of the development of a river, which are the youthful, mature, and old age stages, the old age river is least dynamic
The water is very slow moving with a low gradient and lesser erosive power to alter the landscape which results in the appearance of flood planes
Examples of old age rivers include, lower Ganges, lower Nile, Indus, and Yellow rivers
Old age rivers are characterized by a broad shape, with a wide flood plane, a very gentle gradient and the water current is low.