Explanation:
<u>Moles is denoted by given mass divided by the molecular mass , </u>
Hence ,
n = w / m
n = moles ,
w = given mass ,
m = molecular mass .
For example ,
For a compound X ,
The given mass i.e. w = 20 g
and the molecular mass ,i.e. , m = 10 g / mol
Then the moles can easily be calculated by using the above formula ,
n = w / m
n = 20 g / 10 g/mol = 2 mol
Hence , answer = 2 mol.
Answer:
they would react to make aluminum oxide and nitrogen
Explanation:
hope this helps plz mark as brainliest
Get a magnet in a bag (inside out) and move the magnet all over the sand/iron and you can collect all the iron and turn the bag right side out and zip up the bag. Now you have the sand and iron separated and it will be harder to accidentally mix them later.
Answer:
11.39
Explanation:
Given that:
Given that:
Mass = 1.805 g
Molar mass = 82.0343 g/mol
The formula for the calculation of moles is shown below:
Thus,
Given Volume = 55 mL = 0.055 L ( 1 mL = 0.001 L)
Concentration = 0.4 M
Consider the ICE take for the dissociation of the base as:
B + H₂O ⇄ BH⁺ + OH⁻
At t=0 0.4 - -
At t =equilibrium (0.4-x) x x
The expression for dissociation constant is:
![K_{b}=\frac {\left [ BH^{+} \right ]\left [ {OH}^- \right ]}{[B]}](https://tex.z-dn.net/?f=K_%7Bb%7D%3D%5Cfrac%20%7B%5Cleft%20%5B%20BH%5E%7B%2B%7D%20%5Cright%20%5D%5Cleft%20%5B%20%7BOH%7D%5E-%20%5Cright%20%5D%7D%7B%5BB%5D%7D)
x is very small, so (0.4 - x) ≅ 0.4
Solving for x, we get:
x = 2.4606×10⁻³ M
pOH = -log[OH⁻] = -log(2.4606×10⁻³) = 2.61
<u>pH = 14 - pOH = 14 - 2.61 = 11.39</u>
From Earth's<span> density we can estimate what elements must compose the </span>Earth; an iron core<span> just happens to estimate </span>Earth's<span> mass the best. Now from energy waves, geologists use seismometers to measure movements in </span>Earth's<span> interior (e.g. Earthquakes), These energy-waves form compressional and shear waves</span>
