Answer:
A mature stem that has thick bark
Explanation:
i dont know but that is what i put on my test but if you had your awnser right tell me
Answer:
1. 6.005 g
2. 22.9 mL
3. Until the mixtures becomes homogeneous.
Explanation:
A buffer is a solution where a weak acid is in equilibrium with its conjugate base (its anion) or a weak base is in equilibrium with its conjugate base (its cation). The buffer remains the pH almost unaltered because it shifts the equilibrium if an acid or base is added.
1. The pH of a buffer can be calculated by the Henderson-Hasselbalch equation:
pH = pKa + log[A⁻]/[HA]
Where [A⁻] is the concentration of the conjugate base (the anion) of the acid, and HA is the acid concentration.
5.10 = 4.76 + log[A⁻]/[HA]
log[A⁻]/[HA] = 5.10 - 4.76
log[A⁻]/[HA] = 0.34
[A⁻]/[HA] =
[A⁻]/[HA] = 2.1878
Because the volume is the same, we can replace the concentration by the number of moles (n):
nA⁻/nHA = 2.1878
nA⁻ = 2.1878*nHA
The total number of moles of the substances in the buffer is: 0.200 mol/L * 0.5 L = 0.1 mol
nA⁻ + nHA = 0.1
2.1878*nHA + n HA = 0.1
3.1878nHA = 0.1
nHA = 0.0314 mol
nA⁻ = 0.0686 mol
The total number of moles of acetic acid needed is 0.1 mol (both substances may be from it):
m = MW*mol
m = 60.05*0.1 = 6.005 g
2. NaOH must react with acetic acid to form the anion, so for a 1:1 reaction, it will be needed 0.0686 mol of NaOH:
V = mol/concentration
V = 0.0686/3
V = 0.0229 L = 22.9 mL
3. The buffer must be a homogeneous solution, it means that it can't be noticed phases in the buffer, so the flask must be inverted until all the buffer is diluted in water, and it will be noticed when the solution becomes homogenous.
First we need to find the limiting reactant. This is the reactant that is theoretically consumed completely first. Theoretical yield is how much product is produced given the limiting reactant is consumed and the percent yield is the fraction of the actual products produced and the theoretical products produced.
The limiting reactant is <span>Pb(<span>C2</span><span>H3</span><span>O2</span><span>)2.
The theoretical yield is </span></span>1.2373008g and you should get the Percent yield which is Actual yield/theoretical yield. <span />
Answer:
1/A
Explanation:
beuse the golf ball has mor mass it would take a push from your hand but for the talbe tennis all you need is even a littel flick to it.
The correct answer is A. It shows how electrons are distributed in the shells of an iron atom.
Explanation:
In the model described, the circles represent the orbitals or shells of the atom, while the dots represent the distribution of electrons (negatively charged sub-particles). Additionally, the description shows the general electronic configuration of this atom is 2, 8, 14, 2, which means in the first orbital there are two electrons, in the second there are eight electrons, in the third, there are fourteenth electrons and in the fifth orbital there are two electrons. This electronic configuration occurs in the atoms of iron. Also, this differs from Cobalt because in cobalt the third orbital has 15 electrons. Thus, the model "shows how electrons are distributed in the shells of an iron atom".