Answer:
Water has the unique ability to dissolve many polar and ionic substances. This is important to all living things because, as water travels through the water cycle, it takes many valuable nutrients along with it! Water has high heat capacity.
Explanation:
Answer:
Thus, the radius of the helium atom in nanometers is - 0.031 nm
Explanation:
Given that:-
The radius of the helium atom = 31 pm
Considering the conversion of length in pm to the length in nm as:-
1 pm = 0.001 nm
So,
Applying the above conversion factor in the radius of helium atom as:-
Radius = nm = 0.031 nm
<u>Thus, the radius of the helium atom in nanometers is - 0.031 nm</u>
First, we write out a balanced equation.
HA <--> H(+) + A(-)
Next, we create an ICE table
HA <--> H+ + A-
[]i 0.40M 0M 0M
Δ[] -x +x +x
[]f 0.40-x x x
Next, we write out the Ka expression.
Ka = [H+][A-]/[HA]
Ka = x*x/(0.40-x)
However, because Ka is less than 10^-3, we can assume the amount of dissociation is negligible. Thus,
Assume 0.40-x ≈ 0.40
Therefore, 1.2x10^-6 = x^2/0.40
Then we solve for the [H+] concentration, or x
x=6.93x10^-4
Next, to find pH we do
pH = -log[H+]
pH = -log[6.93x10^-4]
pH = 3.2
Answer:
Option C: sodium and potassium
Explanation:
Elements in same group having same properties. In given option Only C is the correct option because sodium and potassium are present in same group i.e, group 1 and thus shows similar reactive properties. Bothe are alkali metal and have one valance electron. These are very reactive and can not found in free state in nature but present in compounds.
They react with halogens and form salts.
2Na + Cl₂ → 2NaCl
2K + Cl₂ → 2KCl
All other options are incorrect because,
Option A = Fluorine and neon
Both are present in different group. Fluorine is present in group 17 and neon in group 18 thus their reactivity is not similar.
Option B = Hydrogen and helium
Both are present in different group. Hydrogen is present in group 1 and helium in group 18 thus their reactivity is not similar.
Option D: Aluminum and chlorine
Both are present in different group. Aluminum is present in group 13 and chlorine in group 17 thus their reactivity is not similar.
All these three options are incorrect.