solution:
You need to find the frequency, and they have already given you the wavelength. And since you already know the speed of light, you can use formula (2) to answer this problem. Remember to convert the nano meters to meters because the speed of light is in meters. 

When the salt AgI dissolves, it dissociates as follows;
AgI --> Ag⁺ + I⁻
molar solubility of salt is the amount of salt that can be dissolved in 1 L of solution
since the ions dissociated are in 1:1 molar ratio, the molar solubility of the ions are equivalent to the molar solubility of the salt.
ksp is the solubility product constant of the salt
ksp = [Ag⁺][I⁻]
ksp = (9.1 x 10⁻⁹ mol/L)²
ksp = 8.28 x 10⁻¹⁷
Answer:
their density is only lighter than water because of the air inside. without the air you would sink even if you were holding it firmly.
Explanation:
MgCl₂ & PbSO₄ is the correct product for the given double replacement reaction.
<h3>What is double displacement reaction?</h3>
In the double displacement reaction displacement of two substrate will take place among two reactants and formation of products takes place.
In the question, PbCl₂ reacts with MgSO₄ and displacement between the cations takes place and formation of MgCl₂ and insoluble precipitate PbSO₄ is formed.
Given reaction is represented as:
PbCl₂ + MgSO₄ → MgCl₂ + PbSO₄
According to the activity series, reactivity of Magnesium is more as compared to the lead atom. So lead is displaced by the magnesium atom and form the above given products.
Hence, option (3) is correct i.e. MgCl₂ & PbSO₄.
To know more about double displacement reaction, visit the below link:
brainly.com/question/26413416