Answer : The correct option is, (D) CO₂, BCl₃, and Fe³⁺
Explanation :
According to the Lewis concept, an acid is defined as a substance that accepts electron pairs and base is defined as a substance which donates electron pairs.
(a) 
It is a Lewis-acid because it can accepts electron pairs.
(b) 
It is not a Lewis-acid because it can not accepts electron pairs but it is a base because it can donates and accept hydrogen ion.
(c) 
It is a Lewis-acid because it can accepts electron pairs because it has an incomplete octet and an empty 2p orbital.
(d) 
It is a Lewis-acid because it can accepts electron pairs.
Hence, the ions which behave as Lewis acids are, CO₂, BCl₃, and Fe³⁺
Their atomic number increases
Earth can be divided into three main layers: the core, the mantle and the crust. Each of these layers can be further divided into two parts: the inner and outer core, the upper and lower mantle and the continental and oceanic crust. Both the inner and outer core are made up of mostly iron and a little bit of nickel.
Answer:
The concentration is 4.16 grams per liter, we call the solution saturated.
Explanation:
Step 1: Data given
The solubility of calcium chromate in water is 4.16 grams per liter.
Saturated Solution : A solution with solute that dissolves until it is unable to dissolve anymore, leaving the undissolved substances at the bottom.
Unsaturated Solution: A solution (with less solute than the saturated solution) that completely dissolves, leaving no remaining substances.
Supersaturated Solution: A solution (with more solute than the saturated solution) that contains more undissolved solute than the saturated solution because of its tendency to crystallize and precipitate.
Step 2:
If the calcium chromate solution has a concentration of 4.16 grams per liter.
If the concentration is less than 4.16 grams per liter, we call it unsaturated.
If the concentration is more than 4.16 grams per liter, we call it supersaturated.
The concentration is 4.16 grams per liter, we call the solution saturated.