They start with the numbers u need to know in order to slove the problem and there has to be a story behind it
Answer:K2X
Explanation: Valency can be defined as the combining power of an element. It is the valency that dictates the value an element will have when writing a chemical formula for its compound.
MgX is a compound of magnesium and an element X. The valency of magnesium in most of its compound is +2. Now for the 2 to have been absent in the chemical formula, this shows that the element X itself have a valency if -2 for the valencies of both to have canceled out.
Now considering the element potassium, it is an alkaline metal belonging to group 1 of the periodic table. Hence, it is expected that it has a valency of +1
Forming a compound with element X means there would be an exchange of valencies between the two. We have established that x has a valency of -2. The formula of the compound thus formed by exchanging the valencies of both element would be K2X
Molten barium chloride is separeted
into two species :
BaCl₂(l) → Ba(l) + Cl₂(g),
but first ionic bonds in this salt are separeted because of heat:
BaCl₂(l) → Ba²⁺(l) + 2Cl⁻(l).
Reaction of reduction at cathode(-): Ba²⁺(l) + 2e⁻ → Ba(l).
Reaction of oxidation at anode(+): 2Cl⁻(l) → Cl₂(g) + 2e⁻.
<span>The anode is positive and the cathode is negative.</span>
<u>Answer:</u> The molecular weight of protein is 
<u>Explanation:</u>
To calculate the concentration of solute, we use the equation for osmotic pressure, which is:
or,
where,
= Osmotic pressure of the solution = 0.0861 atm
i = Van't hoff factor = 1 (for non-electrolytes)
= mass of protein = 400 mg = 0.4 g (Conversion factor: 1 g = 1000 mg)
= molar mass of protein = ?
= Volume of solution = 5.00 mL
R = Gas constant = 
T = temperature of the solution = ![25^oC=[25+273]K=298K](https://tex.z-dn.net/?f=25%5EoC%3D%5B25%2B273%5DK%3D298K)
Putting values in above equation, we get:
Hence, the molecular weight of protein is
Answer:
I would go with the first option. It shows how people having been releasing more and more carbon dioxide into the atmosphere.
Explanation:
