Answer:
no of moles = (mass) ÷ molar mass
you get the molar mass from the periodic table
n = 20.0g ÷ ( 149.09 g/mol )
= 0.134 mol
number of formula units = number of moles × (6.022×10^23)
= 8.07×10^22 units
number of hydrogen atoms in (NH4)3 PO3 = 12 × number of formula units
= 9.68×10^23 hydrogen atoms
Salt lowers the freezing/melting point of water, so in both cases the idea is to take advantage of the lower melting point. Ice forms when the temperature of water reaches 32 degrees Fahrenheit (0 degrees Celsius).
Answer:
Decomposition or cracking
Explanation:
Decomposition reaction is a chemical change in which a single compound is broken down into two or more simpler products.
For example;
A → B + C
The driving force of such reaction is the high positive heat of formation of the compound which indicates that they are highly unstable.
Some stable compounds also decompose when subjected to high temperature and pressure.
Friction because smooth ice provides very little resistance against objects, like ice skates being dragged across its surface.