Is easy for regular. If you are taking AP, it’s hard.
What kind of bears dissolve in water?
Polar bears
Expression for the Balmer series to find the wavelength of the spectral line is as follows:
1 / λ = R
Where, λ is wavelength, R is Rydberg constant, and n is integral value (4 here → Fourth level)
Substitute 1.097 x 10⁷ m⁻¹ for R and 4 for n in the above equation
1 / λ = (1.097 x 10⁷ m⁻¹)
= 0.20568 x 10⁷ m⁻¹
λ = 4.86 x 10⁻⁷ m
since 1 m = 10⁹ nm
λ = 486 nm
pH of mixed solution = 4.3
<h3>Further explanation
</h3>
A buffer solution is a solution that can maintain a good pH value due to the addition of a little acid or a little base or dilution.
The buffer solution can be acidic or basic
Acid buffer solution consists of weak acids and their salts.
valence according to the amount of salt anion
mol CH₃COOH = 25 ml x 0.9 = 22.5 mlmol
mol NaOH = 25 ml x 0.45 = 11.25 mlmol
ICE method :
Reaction
NaOH + CH₃COOH ---> CH₃COONa + H₂O
11.25 22.5
11.25 11.25 11.25 11.25
11.25 11.25 11.25
mol acid = 11.25, mol salt = 11.25, Ka CH₃COOH = 5.10⁻⁵
Then [H⁺]=
2 would be the correct answer
The property of mixture which describes a mixture are it can be separated by physical methods, it can appear different from different sources and it cannot be described by a chemical symbol or formula.
<h3>What are mixtures?</h3>
Mixtures are the compounds which are formed by the addition or combination of one or two elements or compounds.
As in the mixtures many states of matters are present and it will be filtered by using various physical methods, and it is not chemically shown by single chemical symbol or formula. Mixtures are also of two types:
- Homogeneous mixtures are those in which equal compositions all over the volume is present.
- Heterogeneous mixtures are those in which different composition all over the volume is present.
Hence options (1), (3) and (4) are correct.
To know more about mixtures, visit the below link:
brainly.com/question/24647756