Answer:
There are five signs of a chemical change:
Colour Change.
Production of an odour.
Change of Temperature.
Evolution of a gas (formation of bubbles)
Precipitate (formation of a solid).
It has to be A or B bc c and d are just dumb answers
I think the correct answer from the choices listed above is option B. <span>Of its 6 electrons, 4 are valence electrons, a carbon atom can form 4 covalent bonds with other elements. It is the 4 valence electrons available that allows this.
Hope this answers the question.</span>
