Answer:
Molecular formula = C₁₀H₂₀
Explanation:
Given data:
Empirical formula = CH₂
Molar mass = 140.27 g/mol
Molecular formula = ?
Solution:
Molecular formula = n (empirical formula)
n = molar mass of compound / empirical formula mass
Now we will calculate the empirical formula mass.
CH₂ = 12 × 1 + 1× 2
CH₂ = 12 +2
CH₂ = 14
n = 140.27 / 14
n = 1
0
Molecular formula = n (empirical formula)
Molecular formula = 10 (CH₂)
Molecular formula = C₁₀H₂₀
1) The elements making up the unknown substance almost always include carbon and hydrogen. Oxygen is often involved and nitrogen is involved sometimes. Other elements can be involved, but problems with C and H tend to predominate followed by C, H and O and then by C, H, O and N.
2) We must know the mass of the unknown substance before burning it.
3) All the carbon in the sample winds up as CO2 and all the hydrogen in the sample winds up as H2O.
4) If oxygen is part of the unknown compound, then its oxygen winds up incorporated into the oxides. The mass of oxygen in the sample will almost always be determined by subtraction.
5) Often the N is determined via a second experiment and this introduces a bit of complexity to the problem. Nitrogen dioxide is the usual product when nitrogen is involved. Sometimes the nitrogen product is N2, sometimes NH3.
6) Sometimes the problem asks you for the empirical formula and sometimes for the molecular formula (or both). Two points: (a) you have to know the molar mass to get to the molecular formula and (b) you have to calculate the empirical formla first, even if the question doesn't ask for it. A few lines below is a link that goes to a file that discusses how to go from empirical to molecular formulas.
Answer:
A white dwarf is what stars like the Sun become after they have exhausted their nuclear fuel. Near the end of its nuclear burning stage, this type of star expels most of its outer material, creating a planetary nebula. Only the hot core of the star remains. ... That means a white dwarf is 200,000 times as dense.
Explanation:
they are cold
they are about the size of Earth
these both are not true
<span>N2</span>+3<span>H2</span>→2N<span>H<span>3 hope this helps
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