Number of atoms is 10 to the 24 power
The correct answers are:
- Only about 3 percent of Earth's water is freshwater;
The amount of freshwater, out of all the water on the planet, is very low, only around 3%. Considering how much we spend of it, and how much we are polluting it, it is alarming, and urgent measures have to be taken in order to preserve this essential life element.
- About 75 percent of the freshwater on Earth is frozen in ice sheets;
Not just being only 3% out of the total water reserves on the planet, the majority of the freshwater is not actually usable, as around 75% (68.7% by the newest data) of it is actually frozen. The ice sheets on the poles, as well as the glaciers, are holding most of the freshwater in them, and even if they melt, the water will become saline and not usable because it will mix with the ocean waters.
The energy level necessary to enable a reaction to occur is called the activation.
True! The activation energy is needed to start a reaction.
Answer:
True
Explanation:
I guessed XD But I also used Google and that's what I got
Answer:
The mass number (A), also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. The mass number is different for each different isotope of a chemical element.
