Answer:
Any binary molecular compound of hydrogen and a Group 6A element above Selenium will be less acidic, so water and dihydrogen sulfide are less acidic in aqueous solution than hydrogen selenide.
Explanation:
Going down in a group increases the atomic radius and a greater atomic radius implyes greater ionic radius.
When ionization takes place in these compounds they yelds protons (hidrogen ion) and an lewis base (anion). The greater the ionic radius the greater its stability, thus the periodic tendency is increaing the acidity of binary hidrogen compounds when going down a group. On the other hand going up a group decreases acidity, so any molecular compound of hydrogen and a Group 6A element above Selenium will be less acidic, so water and dihydrogen sulfide are less acidic in aqueous solution than hydrogen selenide.
Answer:
The answer to your question is Covalent
Explanation:
Both, Hydrogen and Chlorine are non metals, when two nonmetals attach the share electrons and the type of bonding formed is polar covalent because they have different sizes, hydrogen is smaller than chlorine.
Given information : Sample of 
We need to find the moles of Chlorine in the given sample.
We can say that we need to find moles from the given atoms.
Relation between mole and atom is given by : 
Where
is Avogadro number.


On solving the above equation , atoms(unit) gets cancelled out and we get 0.0286 mol.
In the given sample the moles of Chlorine (Cl) is 0.0286 mol , so option A is correct.
k=.240/(.4)^2=1.5 assuming [A]2 means [A] squared