a substance dissolves.
like adding a soluble salt to water, it just dissolves, i.e dissociates homogeneously as water is able to dissociate salts (ionic compounds) into its ions. (it can also dissociate other non-ionic compounds like HCL)
the salt still remains chemically as a salt and is unchanged chemically thus it is not an indication of a chemical reaction as no chemical reaction has taken place.
the formation of a precipitate is a chemical reaction because a new substance (i.e new chemical) is formed. For example adding aqueous sodium hydroxide into an aqueous solution with CU2+ cations will form a blue precipitate (that is copper (II) hydroxide which is insoluble, hence it precipitates). Since a new chemical is formed, a chemical reaction has taken place and thus indicates a chemical reaction.
color change... im not sure but usually a color change will only occur when a new substance is formed. Like iron corrodes (i.e rust) slowly in moist air to form hydrated iron (III) oxide that is rust. (brown color).
usually adding a mixture to a mixture has little energy change, i.e little heat taken in by the reaction mixture or little heat given out by the reaction mixture. Whereas when a new substance is formed, there is usually noticeable energy change like the container gets colder or hotter (without heat being supplied of course). For example dissolving basic oxides into water releases energy ( more energy released than gained = exothermic reaction).
i think that should be the answer... hope it helped :D
Explanation:
Below is an attachment containing the solution.
Answer:
(a) The range of the projectile is 31,813.18 m
(b) The maximum height of the projectile is 4,591.84 m
(c) The speed with which the projectile hits the ground is 670.82 m/s.
Explanation:
Given;
initial speed of the projectile, u = 600 m/s
angle of projection, θ = 30⁰
acceleration due to gravity, g = 9.8 m/s²
(a) The range of the projectile in meters;
(b) The maximum height of the projectile in meters;
(c) The speed with which the projectile hits the ground is;
Answer:
10g
Explanation:
As the Law of Conservation of Mass states that " Mass can neither be created nor be destroyed in a chemical reaction".
Though melting of tin isn't a chemical change, the same logic is applied here...
Hence,
The mass of tin will be 10 g itself...
Answer:
it gets hot and more hot until it turns to gas
Explanation:
