Answer:
28.93 g/mol
Explanation:
This is an extension of Graham's Law of Effusion where 
We're only talking about molar mass and time (t) here so we'll just concentrate on
. Notice how the molar mass and time are on the same position, recall effusion is when gas escapes from a container through a small hole. The time it takes it to leave depends on the molar mass. If the gas is heavy, like Xe, it would take a longer time (4.83 minutes). If it was light it would leave in less time, that gives us somewhat an idea what our element could be, we know that it's atleast an element before Xenon.
Let's plug everything in and solve for M2. I chose M2 to be the unknown here because it's easier to have it basically as a whole number already.

The square root is easier to deal with if you take it out in the first step, so let's remove it by squaring each side by 2, the opposite of square root essentially.



M2= 0.22 x 131
M2= 28.93 g/mol
Answer is: mass of butane is D)11.6 g.
m(butane) = 50,0 g.
V(CO₂) = 17,9 L.
n(CO₂) = V(CO₂) ÷ Vm.
n(CO₂) = 17,9 L ÷ 22,4 L/mol.
n(CO₂) = 0,8 mol.
From chemical reaction n(CO₂) : n(C₄H₁₀) = 8 : 2.
n(C₄H₁₀) = 0,8 mol ÷ 4.
n(C₄H₁₀) = 0,2 mol.
m(C₄H₁₀) = n(C₄H₁₀) · M(C₄H₁₀).
m(C₄H₁₀) = 0,2 mol · 58 g/mol.
m(C₄H₁₀) = 11,6 g.
Explanation:
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<em>tHx</em><em> </em><em>fOr</em><em> pOinTs</em><em>.</em><em>.</em><em>.</em>
<span>Most bonds are made when a positive atom or molecule (one that is missing an electron in its outer shell) accepts an electron from a negative atom or molecule. Hydrogen is a positive ion because it only has one electron in its outer shell instead of a pair. Oxygen has paired electrons, but because it is highly electronegative one of the outer electrons is held closer to the nucleus, creating a partial negative charge. This partial negative charge attracts the electron in the outer shell of hydrogen and creates a bond. This type of bond accounts for the high surface tension in water.</span>