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
Answer: Molecular mass of the phenol is 94g/mol.
Explanation:
Phenol is an active ingredient in some oral anesthetics used in sore throat sprays.It is used as anesthetics to cure minor sour throat pain , minor mouth irritations etc.
For Example : Cramex , Chloraseptic sprays contains phenol as an active ingredient.
Phenol has a molecular formula of 
Molecular mass of the phenol = 6(mass of carbon)+5(mass of hydrogen)+1(mass of oxygen)+1(mass of hydrogen) = 6(12)+5(1)+1(16)+(1) = 94 g/mol
Answer:
a) heat it from 23.0 to 78.3
q = (50.0 g) (55.3 °C) (2.46 J/g·°C) =
b) boil it at 78.3
(39.3 kJ/mol) (50.0 g / 46.0684 g/mol) =
c) sum up the answers from the two calculations above. Be sure to change the J from the first calc into kJ
Explanation:
In the modern periodic table when elements are arranged according to their atomic number.