Water Flashcards
What is insoluble in water?
Covalent network solids due to the covalent bonds in their lattices which are too strong for water to break. The same occurs with covalent layer solids and most non-polar substances.
What anions are soluble?
Chlorine, bromine, iodine, nitrate and sulfate. All nitrates are soluble but there are some exceptions to each such as silver, mercury and lead.
What anions are insoluble?
Phosphate, carbonate, hydroxide and sulfide but most are soluble when with elements in the first group or ammonium (NH4).
What are half equations?
Generally show the gaining or loss of electrons. They always are shown with electrons being added so if it is lost we see it being split.
E.g. Mg becomes Mg2+ + 2e-
2H+ + 2e- becomes H2 gas
2Cl- remains a spectator ion
What are full and net ionic equations?
Full ionic: shows all ions
Net ionic: shows only ions that form solid.
What is concentration?
Concentration is the amount of solute in a specified amount of solvent or solution also known as the molarity (mol L-1)
This is expressed as:
%(w/w) mass of solute per 100g solution
Ppm parts per million
What formulas are used to find concentration?
c1xm1=c2xm2 which can also be used to find the required amount to create another solution.
C=n/v which can be arranged as n=cv for moles or v=n/c for volume.
What is surface tension?
The resistance of a liquid to increase its surface temperature. In water this is due to the strong hydrogen bonds.
What is viscosity?
A measure of resistance of a liquid. The higher the less it flows such as honey.
What happens to the freezing and boiling points of water when a substance is added?
The freezing point decrease and the boiling point increase due to a disruption.
What is the thermal conductivity or specific heat capacity of water?
4.18 J K-1 g-1 which is 4.18 joules per gram to increase by one kelvin.
Why is water considered an important solvent?
Ionic solids are soluble in water due to water’s polar molecules. Polar molecules are generally soluble in water. However some non-polar substances are slightly soluble.
