Answer:
A. releases a large amount of heat
Explanation:
A reaction is said to be spontaneous if it can proceed on its own without the addition of external energy. A spontaneous reaction is not determined by the length of time, because some spontaneous reactions are completed after a long period of time. They are exothermic in nature. An example is the conversion of graphite to carbon which takes a long period of time to complete. Spontaneous reactions are known to increase entropy in a system. Entropy is the rate of disorder in a system.
In the combustion of fire, energy is released to the surroundings as there is a decrease in energy. This is an example of a spontaneous reaction because it is an exothermic reaction, which causes an increase in entropy and a decrease in energy.
Natural diamonds are made very deep within earth's surface where high temperatures and pressure exist naturally, thus making them much more difficult to obtain, and making them a more expensive option that Swarovski Crystal.
Answer:

Explanation:
Hello,
In this case, since the density is defined as the ratio between the mass and the volume as shown below:

We can compute the density of water for the given 43 g that occupy the volume of 43 mL:

Regards.
Ice floats because it is about 9% less dense than liquid water. ... The heavier water displaces the lighter ice, so ice floats to the top. One consequence of this is that lakes and rivers freeze from top to bottom, allowing fish to survive even when the surface of a lake has frozen over