First, we need to get moles of NaOH:
when moles NaOH = volume * molarity
= 0.02573L * 0.11 M
= 0.0028 moles
from the reaction equation:
H3PO4(aq) + 3NaOH → 3 H2O(l) + Na3PO4(aq)
we can see that when 1 mol H3PO4 reacts with→ 3 mol NaOH
∴ X mol H3PO4 reacts with → 0.0028 moles NaOH
∴ moles H3PO4 = 0.0028 mol / 3 = 9.4 x 10^-4 mol
now we can get the concentration of H3PO4:
∴[H3PO4] = moles H2PO4 / volume
= 9.4 x 10^-4 / 0.034 L
= 0.028 M
The molar mass of the gas is 77.20 gm/mole.
Explanation:
The data given is:
P = 3.29 atm, V= 4.60 L T= 375 K mass of the gas = 37.96 grams
Using the ideal Gas Law will give the number of moles of the gas. The formula is
PV= nRT (where R = Universal Gas Constant 0.08206 L.atm/ K mole
Also number of moles is not given so applying the formula
n= mass ÷ molar mass of one mole of the gas.
n = m ÷ x ( x molar mass) ( m mass given)
Now putting the values in Ideal Gas Law equation
PV = m ÷ x RT
3.29 × 4.60 = 37.96/x × 0.08206 × 375
15.134 = 1168.1241 ÷ x
15.134x = 1168.1241
x = 1168.1241 ÷ 15.13
x = 77.20 gm/mol
If all the units in the formula are put will get cancel only grams/mole will be there. Molecular weight is given by gm/mole.
Answer:
- <u><em>You should expect that the ionic bond in LiBr is stronger than the bond in KBr.</em></u>
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Explanation:
The<em> ionic bonds</em> are formed by the electrostatic attraction between the ions, cations and anions.
In KBr the cation is K⁺ and the anion is Br⁻.
In LiBr the cation is Li⁺ and the anion is Br⁻.
You must expect that the bond strength depends mainly on the charges present on each ion and the distance between them.
Nevertheless, the effect of the distance between the radius dominate the trendency of the bond strength, which makes that the ionic strength trend be related to the ionic radius trend.
Lithium is a smaller ion than Potassium (both are in the same group and Lithium is above Potassium).
Thus, you should expect that the Li ion is closer to the Br ion than what the K ion is to the Br ion and expect that the bond between a Li ion and the Br ion be stronger than the bond between the K ion and the Br ion.
They are like carried by the convection in the mantle which is pulsing or pushing the plates upwards. the earth kind of "floats" in ways. mostly its just pressure from the mantle and center of the earth pushing the plates upward and out.
