Answer:
- <em><u>oxygen atoms</u></em>
Explanation:
Electronegativity measures the relative strength with which the different elements attract the electrons in a covalent bond.
So, being oxygen more electronegative than hydrogen, the electrons in a water molecule (H₂O or H - O - H) are more strongly attractet by the oxygen atoms, which means that <em>the electrons will spend more time closer to oxygen atoms than to hydrogen atoms</em>.
As result of the <em>electrons spending more time closer to the oxygen atoms</em>, there will exist a partial negative charge over the oxygen atoms whiile there will be a partial positive charge over the hydrogen atoms.
Hence, the bond formed between oxygen and hydrogen atoms in a water molecules is a polar covalent bond.
You can read more about electronegativity and polar covalen bonds on brainly.com/question/12488329.
Answer:
Excited state of an electron is the state attained by an electron after it has absorbed energy and it moves further from the nucleus.
an electron is at higher energy when excited and at lower energy when at ground state.
an excited electron is less stable due to the decrease in the nuclear force of attraction and the grounded electron is more stable due to it's close distance to the nucleus.
According to Henderson–Hasselbalch Equation,
pH = pKa + log [Nitrate] / [Nitric Acid]
As, Ka of Nitric Acid = 7.1 × 10⁻⁴
So,
pKa = -log [ 7.1 × 10⁻⁴ ]
pKa = 3.148
So, pH = 3.148 + log [Nitrate] / [Nitric Acid]
3.90 = 3.148 + log [Nitrate] / [Nitric Acid]
3.90 - 3.148 = log [Nitrate] / [Nitric Acid]
0.752 = log [Nitrate] / [Nitric Acid]
Taking Antilog on both sides,
[Nitrate] / [Nitric Acid] = 5.64
For this question, assume that you have 1 compound. This compound is divided in half once, so you are left with 0.5. That 0.5 that remains is divided in half again, this is the second half-life, and you are left with 0.25. The final half life involves dividing 0.25 in half, which means you are left with 0.125. For the answer to make sense, you need to know your conversions between decimals and fractions. To make it simple, if you have 0.125 and you times it by 8, you are left with your initial value of 1. Therefore, after three half-lives, you are left with 1/8th of the compound.
