Answer:
Evaporation and gravity cause water to move through the water cycle.
Explanation:
Evaporation turns liquid water into a gas, and brings it up into the atmosphere, where the gas condenses into frozen water molecules, which stick to each other. When a clump of water molecules gets too heavy, gravity pulls them down to the surface as precipitation. Depending on the temperature, the frozen water droplets may melt, or stay frozen.
Gravity brings precipitation to the ground.
Water has to heat up from high temperature, from either the sun or another heat source, to change the form from gas to liquid.
Water vapor must get to a certain temperature of cold to freeze, causing it to condense from a gas to liquid.
Thermal energy causes evaporation of water, which allows the water to be reprecipitated once again.
Answer:
a)22.2°C after adding magnesium
b)17.3°C before adding magnesium
c) 4.9 is change
Answer:
1. hydrogen - H
2. helium - He
3. sodium - Na
4. magnesium - Mg
5. potassium - K
Explanation:
Hydrogen is the element of group 1 and first period. The atomic number of hydrogen is 1 and the symbol of the element is H.
The electronic configuration of the element hydrogen is:-

Helium is the element of group 18 and first period. The atomic number of helium is 2 and the symbol of the element is He.
The electronic configuration of the element helium is:-

Sodium is the element of group 1 and third period. The atomic number of sodium is 11 and the symbol of the element is Na.
The electronic configuration of the element sodium is:-

Magnesium is the element of group 2 and third period. The atomic number of magnesium is 12 and the symbol of the element is Mg.
The electronic configuration of the element magnesium is:-

Potassium is the element of group 1 and forth period. The atomic number of potassium is 19 and the symbol of the element is K.
The electronic configuration of the element potassium is:-

Hello there!
To determine the fraction of the hydrogen atom's mass that is in the nucleus, we have to keep in mind that
a Hydrogen atom has 1 proton and 1 electron.
Protons are in the nucleus while electrons are in electron shells surrounding the nucleus.
The mass of the nucleus will be equal to the mass of 1 proton and we can express the fraction as follows:

So, the fraction of the hydrogen atom's mass that is in the nucleus is
0,9995. That means that almost all the mass of this atom is at the nucleus.
Have a nice day!