Most likely decreased birth rate and increased emigration.
Answer:
A. Na₂SO₄ and HCl
C. Polar solutes are soluble in polar solvents but are insoluble in non-polar solvents Non-polar solutes are insoluble in polar solvents but are are soluble in non-polar solvents
Ionic solutes are soluble in polar solvents but are insoluble in non-polar solvents.
Like dissolves like simply means that molecules of substances having similar chemical properties dissolve in each other
Explanation:
A. Ionic substances like Na₂SO₄ are composed of charged particles called ions. These ions are either positively charged or negatively charged, therefore, they are attracted to substances of opposite charges. Also, polar molecules like HCl contains two oppositely charged ends. A polar solvent consists of molecules with two oppositely charged ends, therefore, ionic substances as well polar substances dissolve in them according to the concept of like dissolves like.
Gasoline being non-polar will only dissolve in like substances, polar solvents.
C. Polar solutes are soluble in polar solvents but are insoluble in non-polar solvents Non-polar solutes are insoluble in polar solvents but are are soluble in non-polar solvents
Ionic solutes are soluble in polar solvents but are insoluble in non-polar solvents.
The statement "Like dissolves like" simply means that molecules of substances having similar chemical properties dissolve in each other. For example gasoline, a non-polar substance will dissolve only in a non-polar solvent like kerosene. Also, HCl, a polar molecule will dissolve in a polar solvent like water.
For example...
You have solution with [H+] = 0,01M
>>>> pH = -log[H+] = -log0,01 = 2
And you increase the [H+] by 10x ---> 0,01×10 = 0,1M
>>>> pH = -log0,1 = 1
○ pH decrease by 2x
○ pH is more acidic
C. C and Pb; Carbon and Lead being in the same group.
The percentage of Chromium in Chromium Oxide is calculated as follow,
Step 1: Calculate Molar mass of Cr₂O₃,
Cr = 51.99 u
O = 16 u
So,
2(51.99) + 3(16) = 103.98 + 48 = 151.98 u
Step 2: Secondly divide molar mass of only chromium with total mass of Cr₂O₃ and multiply with 100.
i.e.
=

× 100
=
68.41 %
So, the %age composition of chromium in chromium oxide is
68.41 %.