Answer: Option (d) is the correct answer.
Explanation:
A change that does not cause any difference in chemical composition of a substance are known as physical change.
For example, shape, size, mass, volume, density, etc of a substance are all physical changes.
And, a change that causes changes in chemical composition of a substance is known as chemical change.
For example, precipitation, reactivity, toxicity etc are chemical change.
Therefore, change in temperature, chemical precipitation of a solid
, production of a gas are all indications of a chemical change.
Thus, we can conclude that change in volume would not necessarily indicate a chemical reaction.
Answer:
b. close to 0 degree celsius
Explanation:
100 g * ( x-0)= 500 g * ( 25-x) , where x is the new temperature reached
if we solve for x , we get 20 degree celsius
i.e. the temperature of ice increases to 5 degree celsius and the temperature of water drops to 5 degree celsius
hope it helps.
Answer: H₂O is just water
Explanation:
Answer:
A) homotopic and B) enantiotopic
Explanation:
Protons chemically equivalent are those that have the same chemical shift, also if they are interchangeable by some symmetry operation or by a rapid chemical process.
The existence of symmetry axes, Cn, that relate to the protons results in the protons being homotopic, that is chemically equivalent in both chiral and aquiral environments.
The existence of a plane of symmetry, σ, makes the protons related by it, are enantiotopic and these protons will only be equivalent in an aquiral medium; if the medium is chiral both protons will be chemically NOT equivalent. The existence of a center of symmetry, i, in the molecule makes the related protons through it enantiotopic and therefore chemically only in the aquiral medium.
Diastereotopic protons cannot be interconverted by any symmetry operation and they are different, with different chemical displacement.