Answer:
(d) burning a log.
(b) toasting a slice of bread;
Explanation:
Chemical change -
A chemical change refers to , the change in which a new compound is formed .
From the question ,
Its is not a chemical process , since no new compound is formed , these is only change in state as the liquid is turning to gaseous sate .
It is not a chemical process , as no new substance is formed .
- toasting a slice of bread
It is a chemical change , in which bread surface is deposited by a brown coat via the process of heating , even this process is a irreversible in nature .
It is a chemical change , as with the help of heating , the wood is turning to ashes .
Answer:
he atomic size of an atom, also called the atomic radius, refers to the distance between an atom's nucleus and its valence electrons. Remember, the closer an electron is to the nucleus, the lower its energy and the more tightly it is held
Explanation:
Answer:
positive(cations) and negative(anions)
Explanation:
Basically, this figure represents scattering of alpha particles by the atoms of a gold foil.
- Here, A represents that a few alpha particles are deflected through large angle. It shows that the nucleus of the atom is positively charged which repels the positively charged alpha particles and deflect them from their original path.
- B represents that most alpha particles pass straight through the gold foil without any deflection from their original path. The reason is that there is a lot of empty space in the atom.
- C represents that some alpha particles are deflected through small angles. The reason is same as that of A.
Hope you could understand.
If you have any query, feel free to ask.
There are 1739218 atoms in 2.5 mole of wolframite