<span>Carbon must share 4 electrons total with the the two Oxygen atoms in order to fill it's outer electron shell, and each Oxygen atom must share 2 electrons with the Carbon atom to fill their electron shells. Therefore, in total 8 electrons must be shared (4+2+2=8)</span>
Fluorine is a nonmetal and as such it would need to take in or obtain an electron from a metal to have a stable octet, or full number of 8 electrons in its valence shell. Thus due to the indifference of electrons and protons it becomes an anion, a negatively charged ion.
Answer:
pH = 2.66
Explanation:
- Acetic Acid + NaOH → Sodium Acetate + H₂O
First we <u>calculate the number of moles of each reactant</u>, using the <em>given volumes and concentrations</em>:
- 0.75 M Acetic acid * 50.0 mL = 37.5 mmol acetic acid
- 1.0 M NaOH * 10.0 mL = 10 mmol NaOH
We<u> calculate how many acetic acid moles remain after the reaction</u>:
- 37.5 mmol - 10 mmol = 27.5 mmol acetic acid
We now <u>calculate the molar concentration of acetic acid after the reaction</u>:
27.5 mmol / (50.0 mL + 10.0 mL) = 0.458 M
Then we <u>calculate [H⁺]</u>, using the<em> following formula for weak acid solutions</em>:
- [H⁺] =
Finally we <u>calculate the pH</u>:
Answer: fourth option, 10.8 kJ
Explanation:
The <em>heat of fusion</em>, also named latent heat of fusion, is the amount of heat energy required to change the state of a substance from solid to liquid (at constant pressure).
The data of the <em>heat of fusions</em> of the substances are reported in tables and they can be shown either per mole or per gram of substance.
In this case we have that the<em> heat of fusion for water </em>is reported per mole: <em>6.02 kJ/mole</em>.
The formula to calculate <em>how many kJ of heat (total heat) are needed to completely melt 32.3 g of water, given that the water is at its melting point</em> is:
- Heat = number of moles × heat of fusion
The calculations are:
- number of moles = mass / molar mass
number of moles = 32.3 g / 18.015 g/mol = 1.79 mol
- Heat = 1.79 mol × 6.02 kJ / mol = 10.8 kJ ← answer
