Answer:
Kₐ = 6.7 x 10⁻⁴
Explanation:
First lets write the equilibrium expression, Ka , for the dissociation of hydrofluoric acid:
HF + H₂O ⇄ H₃O⁺ + F⁻
Kₐ = [ H₃O⁺ ] [ F⁻ ] /[ [ HF ]
Since we are given the pH we can calculate the [ H₃O⁺ ] ( pH = - log [ H₃O⁺ ] , and because the acid dissociates into a 1: 1 relation , we will also have [F⁻ ]. The [ HF ] is given in the question so we have all the information that is needed to compute Kₐ.
pH = -log [ H₃O⁺ ]
1.68 = - log [ H₃O⁺ ]
Taking antilog to both sides of this equation:
10^-1.68 = [ H₃O⁺ ] ⇒ 2.1 X 10⁻² M= [ H₃O⁺ ]
[ F⁻ ] = 2.1 X 10⁻² M
Solving for Kₐ :
Kₐ = ( 2.1 X 10⁻² ) x ( 2.1 X 10⁻² ) / 0.65 = 6.7 x 10⁻⁴
(Rounded to two significant figures, the powers of 10 have infinite precision )
Water combines with carbon dioxide to produce slightly acidic groundwater
that dissolves limestone and forms caves.
This is because the reaction between water and carbondioxide to form
bicarbonate ions( HCO₃⁻). The bicarbonate ions dissociate into Hydrogen
atoms thereby increasing the acidity.
The acidic environment results in the formation of acidic groundwater that
dissolves limestone and forms caves.
Read more on brainly.com/question/25385913
Answer:
3.75 g.
Explanation:
<em>mass percent is the ratio of the mass of the solute to the mass of the solution multiplied by 100.</em>
<em />
<em>mass % = (mass of solute/mass of solution) x 100.</em>
<em></em>
mass of calcium nitrite = ??? g,
mass of the solution = 25.0 g.
∴ mass % = (mass of solute/mass of solution) x 100
<em></em>
<em>∴ mass of solute (calcium nitrite) = (mass %)(mass of solution)/100</em> = (15.0 %)(25.0 g)/100 = <em>3.75 g.</em>
Answer:
- smoke
- marshmallow
- paint
- Body spray
Explaination:
Firstly, what are colloids?
Colloids are a mixture of two substances:
- one of those substances are insoluble and inseparable
There are 4 types of colloids:
- Sol- Solid in a liquid
- Emulsion- Liquid in a liquid
- Foam- Gas in solid/liquid
- Aerosol- Solid/liquid in gas
So on to the answers:
- Smoke consists of solid and gas and since the solid is being carried by the gas, it is a solid in a gas (aerosol)
- Marshmellow consists of tiny air bubbles and sugar(solid), the air bubbles is inside the solid making it a gas in a solid (foam)
- Body spray turns gas into liquid after spraying it through the can, making it a liquid in a gas (aerosol)
- Paint dries up to become solid which makes it a solid is a liquid (sol)
Hope y'all understand
the semipermeable membrane surrounding the cytoplasm of a cell.
