<span>B. Osmosis is movement of proteins, and diffusion is movement of water.
</span>
Answer:
How can I tell if a chemical reaction is occurring? A chemical reaction is usually accompanied by easily observed physical effects, such as the emission of heat and light, the formation of a precipitate, the evolution of gas, or a color change.
Explanation:
Answer is: hydrogen bonds.
Hydrogen bond is an electrostatic attraction between two polar groups that occurs when a hydrogen atom (H), covalently bound to a highly electronegative atom such as flourine (F), oxygen (O) and nitrogen (N) atoms.
According to the principle of base pairing hydrogen bonds could form between adenine and thymine (two hydrogen bonds between this nucleobases) and guanine and cytosine (three hydrogen bonds between this nucleobases).
Adenine and guanine are purine derivatives and thymine and cytosine are pyrimidine derivates.
The enthalpy for the reaction : ΔH = -132
<h3>Further explanation</h3>
Given
Reaction and the enthalpy
Required
the enthalpy
Solution
Hess Law
Reaction 1 reverse :
A + B = G + C ΔH = -277
Reactions 2 and 3 remain the same (unchanged)
C + F = A ΔH = 303
D = B + H ΔH = -158
Add up all the reactions and remove the same compound from two different sides
D + F = G + H ΔH = -132
Answer:
The number of moles =
The number of molecules =
Explanation:
Volume of the sphere is given by :
here, r = radius of the sphere
Radius = 3 mm
r = 3 mm
1 mm = 0.01 dm (1 millimeter = 0.001 decimeter)
3 mm = 3 x 0.01 dm = 0.03 dm
r = 0.03 dm
<em>("volume must be in dm^3 , this is the reason radius is changed into dm"</em>
<em>"this is done because 1 dm^3 = 1 liter and concentration is always measured in liters")</em>
(1 L = 1 dm3)
Now, concentration "C"=
The concentration is given by the formula :
This is also written as,
moles
One mole of the substance contain "Na"(= Avogadro number of molecules)
So, "n" mole of substance contain =( n x Na )
Molecules =
molecules
