Answer:
40%
Explanation:
Calculate the percent of the mass that is carbon:
Answer:
True
Explanation:
A mole is defined as 6.02214076 × 1023 of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.
Electronic configuration of the atom describes the arrangemnet of electrons in different shells and subshells ( sublevels).
Now , there are 4 types of sublevels: s, p , d and f . These sublevels have orbital which are spaces with high probability of having an electron and each orbital can have maximum 2 electrons.
Therefore,
s-sublevel has 1 orbital - it can have maximum 2 electrons.
p-sublevel has 3 orbitals - it can have maximum 6 electrons
d-sublevel has 5 orbitals - it can have maximum 10 electrons
f-sublevel has 7 orbitals - it can have maximum 14 electrons.
Hence, the acsending order of sublevels in terms of maximum number of electrons is:
<h2>s < p < d < f</h2>
The properties of a compound are different than the properties of the element that forms it
Using the Henderson-Hasselbalch equation on the solution before HCl addition: pH = pKa + log([A-]/[HA]) 8.0 = 7.4 + log([A-]/[HA]); [A-]/[HA] = 4.0. (equation 1) Also, 0.1 L * 1.0 mol/L = 0.1 moles total of the compound. Therefore, [A-] + [HA] = 0.1 (equation 2) Solving the simultaneous equations 1 and 2 gives: A- = 0.08 moles AH = 0.02 moles Adding strong acid reduces A- and increases AH by the same amount. 0.03 L * 1 mol/L = 0.03 moles HCl will be added, soA- = 0.08 - 0.03 = 0.05 moles AH = 0.02 + 0.03 = 0.05 moles Therefore, after HCl addition, [A-]/[HA] = 0.05 / 0.05 = 1.0 Resubstituting into the Henderson-Hasselbalch equation: pH = 7.4 + log(1.0) = 7.4, the final pH.
