Answer:
Oxygen
Explanation:
Water's formula is H20. Which is two hydrogen and one oxygen.
<u>Answer:</u> The weak bond having slightly positive region and a slightly negative region is polar covalent bond.
<u>Explanation:</u>
Covalent bond is defined as the bond which is formed by the sharing of electrons between the atoms. <u>For Example:</u> HCl, 
etc..
They are of two types:
- <u>Polar covalent bond:</u> This bond is formed when difference in electronegativity between the atoms is present. When atoms of different elements combine, it results in the formation of polar covalent bond.
In this bond, a dipole is created. More electropnegative atom will have a slight negative charge and less electronegative atom will have a slight positive charge. For Example: 
etc..
- <u>Non-polar covalent bond:</u> This bond is formed when there is no difference in electronegativity between the atoms. When atoms of the same element combine, it results in the formation of non-polar covalent bond. For Example:
etc..
Hence, the weak bond having slightly positive region and a slightly negative region is polar covalent bond.
Answer is: concentration of hydrogenium ions is 9,54·10⁻⁵ M.
c(HNO₂) = 0,075 M.
c(NaNO₂) = 0,035 M.
Ka(HNO₂) = 4,5·10⁻⁵.
This is buffer solution, so use <span>Henderson–Hasselbalch equation:
pH = pKa + log(c(</span>NaNO₂) ÷ c(HNO₂)).
pH = -log(4,5·10⁻⁵) + log(0,035 M ÷ 0,075 M).
pH = 4,35 - 0,33.
pH = 4,02.
<span>[H</span>₃O⁺] = 10∧(-4,02).
<span>[H</span>₃O⁺] = 0,0000954 M = 9,54·10⁻⁵ M.
Entropy change is defined only along the path of an internally reversible process path.
<h3><u>What is Entropy Change </u>?</h3>
- Entropy is a measure of a thermodynamic system's overall level of disorder or non-uniformity. The thermal energy that a system was unable to use to perform work is known as entropy.
- Entropy Change is a phenomena that measures how disorder or randomness have changed inside a thermodynamic system.
- It has to do with how heat or enthalpy is converted during work. More unpredictability in a thermodynamic system indicates high entropy.
- Entropy is a state function, hence it is independent of the direction that the thermodynamic process takes.
- The rearranging of atoms and molecules from their initial state causes the change in entropy.
- This may result in a decrease or rise in the system's disorder or unpredictability, which will, in turn, result in a corresponding drop or increase in entropy.
To view more questions about entropy change, refer to:
brainly.com/question/4526346
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