Answer:
a
Explanation:
Each oxygen molecule has 2 hydrogen molecules
If pH is less than seven (pH<7), solution is acidic.
If pH is equal seven (pH = 7), solution is neutral.
If pH is greater than seven (pH > 7), solution is basic.
Some examples:
1) Acidic - gastric juices pH 1, lemon juice pH 2.2, tomato juice pH 4.
2) Neutral - salt solution pH 7.
3) Alkaline - baking soda pH 9, bleach pH 13.
pH is a numeric scale used to specify the acidity or basicity of an aqueous solution.
Answer:
401.17 K is the minimum temperature at which the reaction will become spontaneous under standard state conditions.
Explanation:
The expression for the standard change in free energy is:
Where,
is the change in the Gibbs free energy.
T is the absolute temperature. (T in kelvins)
is the enthalpy change of the reaction.
is the change in entropy.
Given at:-
Temperature = 25.0 °C
The conversion of T( °C) to T(K) is shown below:
T(K) = T( °C) + 273.15
So,
T₁ = (25.0 + 273.15) K = 298.15 K
= 128.9 kJ/mol
= 33.1 kJ/mol
Applying in the above equation, we get as:-
= 0.32131 kJ/Kmol
So, For reaction to be spontaneous, 
Thus, For minimum temperature:-
<u>Hence, 401.17 K is the minimum temperature at which the reaction will become spontaneous under standard state conditions.</u>
Answer:
C). The Bohr-Rutherford model
Explanation:
The 'Bohr-Rutherford model' of the atom failed to elaborate on the attraction between some substances. It essentially targeted hydrogen atoms and failed to explain its stability across multi-electrons. The nature and processes of the chemical reactions remained unillustrated and thus, this is the key drawback of this model. Thus, <u>option C</u> is the correct answer.
When waves bounce back after meeting a surface, it is called Reflection.
