Answer:
I think the answer might be D. but im not 100 percent sure
Explanation:
Explanation:
The valency of the element is the measure of the combining power of the element with the other atoms when the element forms compounds or molecules.
<u>Thus, valency has to known to find the how the elements have been combined and how many electrons have been lost, gain or shared.</u>
Given that:
Element A has 3 valence electrons and element B has 2 valence electrons. To find the ionic compound, the valency of the cations and the anions are interchanged and are written in subscripts. Thus,
A B
3 2
Cross multiplying, we get the formula : 
<u>Hence, 3 is the subscript for Element B.</u>
Answer:
NaOH
Explanation:
In general, Elements of Group IA and Group IIA Hydroxides except for Beryllium Hydroxide are considered to be strong bases.
Answer: Option A) 83.9g
Explanation:
KCl is the chemical formula of potassium chloride.
Given that,
Amount of moles of KCl (n) = ?
Volume of KCl solution (v) = 0.75L
Concentration of KCl solution (c) = 1.5M
Since concentration (c) is obtained by dividing the amount of solute dissolved by the volume of solvent, hence
c = n / v
make n the subject formula
n = c x v
n = 1.5M x 0.75L
n = 1.125 mole
Now given that,
Amount of moles of KCl (n) = 1.125
Mass of KCl in grams = ?
For molar mass of KCl, use the molar masses of:
Potassium, K = 39g;
Chlorine,Cl = 35.5g
KCl = (39g + 35.5g)
= 74.5g/mol
Since, amount of moles = mass in grams / molar mass
1.125 mole = m / 74.5g/mol
m = 1.125 mole x 74.5g/mol
m = 83.81g
Thus, 83.9 grams of KCl are needed to prepare 0.750 L of a 1.50 M solution in water
na look it up please im not that smart