Answer:
the compound contains C, H, and some other element of unknownidentity, so we can’t calculate the empirical formula
Explanation:
Mass of CO2 obtained = 3.14 g
Hence number of moles of CO2 = 3.14g/44.0 g = 0.0714 mol
The mass of the carbon in the sample = 0.0714 mol × 12.0g/mol = 0.857 g
Mass of H2O obtained = 1.29 g
Hence number of moles of H2O = 1.29g/18.0 g = 0.0717 mol
The mass of the carbon in the sample = 0.0717 mol × 1g/mol = 0.0717 g
% by mass of carbon = 0.857/1 ×100 = 85.7 %
% by mass of hydrogen = 0.0717/1 × 100 = 7.17%
Mass of carbon and hydrogen = 85.7 + 7.17 = 92.87 %
Hence, there must be an unidentified element that accounts for (100 - 92.87) = 7.13% of the compound.
Answer:
D) 2-methylpent-2-ene
Explanation:
This is an elimination reaction of Halogenoalkane. 2-bromo-2-methylpentane when is heated with NaOH or NaOC2O5( sodium ethoxide) in ethanol will form alkene rather than alcohol.
2-methylpent-1-ene is minor product since double bond form with secondary Carbon rather than primary Carbon.
Answer:
B. an element
Explanation:
An atom is smallest indivisible particle that takes part in a chemical reaction. Different atoms due to the number of their protons called atomic number gives an element. Every element is a singular atom on it's own. Combination of atoms leads to the formation of molecules and compounds.
When compounds mix together without an actual chemical change, a mixture forms.
Elements are distinct substances that cannot be split up into simpler substances. They are usually made up of only one kind of atom.
In terms of a deeper scientific reason, I am not sure, but the basic reason is quite simple. "Mud" tends to look like a mix between a solid, dirt, and a liquid, water or some other liquid. Since it is, in fact, a cross between a solid and a liquid, it has properties of both. It has certain physical and visual properties that only a solid would have, such as texture and opaqueness, but it also has physical properties of a liquid. Since it leans more towards the liquid side than the solid side, we say mud "flows" rather than saying that it "rolls" or "bounces".
Answer:
The correct row is B.
Explanation:
The formation of the magnesium ion, Mg²⁺, comes from the removal of 2 electrons from the valence shell of the magnesium atom.<em> </em>Since the remotion is of electrons, the nucleus of the atom remains the same, so the number of protons and the number of neutrons does not change.<em> </em>
If the number of proton change, then the atom also change, since the identity of an atom is related to the atomic number which is the same to the proton number.
Now, if the number of neutrons changes, then we would be in the presence of an isotope of the magnesium atom.
Therefore, the correct row is B.
I hope it helps you!
