Water on earth can exist in all 3 states: solid, liquid, and gas.
Earth is just the right distance from the sun so that temperatures are ideal for living organisms.
Earth has a protective atmosphere shielding the planet from harmful UV and X rays.
Answer: 
Explanation:
a) 
: This is a non polar covalent compound which are held by weak vanderwaal forces of attraction.
b) 
: This is a covalent compound which is polar due to the presence of lone pair of electrons and are held by dipole-dipole forces of attraction.
c) : These are joined by a special type of dipole dipole attraction called as hydrogen bond. It forms between electronegative nitrogen atom and hydrogen atom and is the strongest interaction.
d) 
: This is a covalent compound and is non polar which are held by weak vanderwaal forces of attraction.
e) 
: This is a covalent compound and is non polar which are held by weak vander waal forces of attraction.
Answer:
<em>By</em><em> </em><em>Bayer</em><em> </em><em>process</em><em>.</em>
Explanation:
<em>In the Bayer process, bauxite ore is heated in a pressure vessel along with a sodium hydroxide solution (caustic soda) at a temperature of 150 to 200 °C. At these temperatures, the aluminium is dissolved as sodium aluminate (primarily [Al(OH)4]−) in an extraction process.</em>
Answer: b. accepts 
ions from acids
Explanation:
According to Arrhenius concept, a base is defined as a substance which donates hydroxide ions 
when dissolved in water and an acid is defined as a substance which donates hydronium ions 
in water.
According to the Bronsted Lowry conjugate acid-base theory, an acid is defined as a substance which donates ions and a base is defined as a substance which accepts ions.
Here water is donating ions, and thus act as acid and ammoia is accepting ions from water and thus is a base.
According to the Lewis concept, an acid is defined as a substance that accepts electron pairs and base is defined as a substance which donates electron pairs.
Thus base is a substance which accepts ions from acids.
