Answer:
1.55×10²² molecules.
Explanation:
We'll begin by calculating the number of mole in 5.32 g of pure lead (Pb). This can be obtained as follow:
Mass of Pb = 5.32 g
Molar mass of Pb = 207 g/mol
Mole of Pb =?
Mole = mass /molar mass
Mole of Pb = 5.32/207
Mole of Pb = 0.0257 mole
Finally, we shall determine the number of molecules in 0.0257 mole of Pb. This can be obtained as follow:
From Avogadro's hypothesis,
I mole of Pb contains 6.02×10²³ molecules.
Therefore, 0.0257 mole will contain = 0.0257 × 6.02×10²³ = 1.55×10²² molecules.
Therefore, 5.32 g of pure lead (Pb) contains 1.55×10²² molecules.
Answer:
A toilet requires a large amount of cold water to flush. So, when the toilet flushes while you're in the shower, it's stealing from your shower's cold water supply. When the pressure-balancing valve senses the drop in cold water pressure, it responds by restricting the hot water pressure.
In Thomson's experiment, he showed that an electrical current can be made to flow from a positive site to a negative site.
Easy peasy! All we need to do is plug this formula into our calculator:
-log(M)
So, we'd plug in -log(.2), which is 0.7 :)
Answer:
94.61 %
Explanation:
percent yield = (actual yield / theoretical yield) X 100%
The balanced equation for the reaction is:
H2 (g ) + Cl2(g) => 2 HCl (l)
So, the theoretical yield =
7.25g of chlorine X (2mol of Cl / 35.453 g of Cl) X (2mol Cl / 2mol of HCl) X 37.469g of Hcl / 2mol of Hcl = 0.409 x 18.735 = 7.663g of Hcl
Using this theoretical yield and the provided value for actual yield, the percent yield = (actual yield / theoretical yield) X 100%
= (7.25 g / 7.663g) X 100
= 94.61 %