The first one is substance 3
The second one is Oxygen, Helium, and carbon dioxide
The third one is the oil floats on top of the water
Answer:
1. the group number of sodium is 1 and it is a metal
2. the group number of helium is 18 and it is a nonmetal
3. the group number of iodine is 17 and it is a nonmetal
4.the group number of calcium is 2 and it is a metal
5. lithium has similar properties to potassium
6. calcium has similar properties to magnesium
7. neon has similar properties to xenon
8. Iodine has similar properties to chlorine
Answer: released to; absorbed from
- In an exothermic reaction, energy is released to the surroundings.
- In an endothermic reaction, energy is absorbed from the surroundings.
Explanation:
An exothermic reaction is a chemical reaction that occurs spontaneously and brings about the release of energy to the surroundings. Hence, the reacting vessel feels hot as the reaction proceeds.
An endothermic reaction, on the other hand, does not occur spontaneously and proceed only when energy is absorbed from the surroundings. Hence, the reacting vessel feels cold as the reaction proceeds.
The sun, which drives the water cycle, heats water in the oceans. Some of it evaporates as vapor into the air. ... Most precipitation falls back into the oceans or onto land, where, due to gravity, the precipitation flows over the ground as surface runoff.
