Chemistry<span> is often </span>called the central science<span> because of its role in connecting the physical </span>sciences<span>, which include </span>chemistry<span>, with the life </span>sciences<span> and applied </span>sciences<span> such as medicine and engineering.</span>
Answer:
Kₐ = 5.7 x 10⁻⁵
Explanation:
The equilbrium for this acid is
HC₃H₃CO₂ + H2O ⇄ H₃O⁺ + C₃H₃CO₂ ⁻ ,
and the equilibrium constant for acrylic acid is given by the expression:
Kₐ = [ H₃O⁺][ C₃H₃CO₂⁻ ] / [ HC₃H₃CO₂ ]
Since the pH of the 0.23 M solution is known , we can calculate [ H₃O⁺].
The ][ C₃H₃CO₂⁻ ] is equal to [ H₃O⁺] from the above equilibria (1:1)
Finally [ HC₃H₃CO₂ ] is known.
pH = - log [ H₃O⁺]
taking antilog to both sides of the equation
10^-pH = [ H₃O⁺]
Substituting
10^-2.44 = [ H₃O⁺] = 3.6 x 10⁻³
[ C₃H₃CO₂⁻ ] = 3.6 x 10⁻³
Kₐ = ( 3.6 x 10⁻³ ) /0 .23 = 5.7 x 10⁻⁵
Answer: d=2000 g/L
Explanation:
Density is mass/volume. The units are g/L. Since we are given mass and volume, we can divide them to find density. First, we need to convert kg to g.

Now that we have grams, we can divide to get density.

d=2000g/L
Answer : The photon energy of this light in units of nanometers, (nm) is, 
Solution :
Formula used :

where,
E = energy of photon = 
h = Planck's constant = 
c = speed of light = 
= wavelength = ?
Now put all the given values in the above formula, we get:


conversion used : 
Therefore, the photon energy of this light in units of nanometers, (nm) is, 