Post an answer to the following 6 mark question in the comments section (remember to put your name on your post).
You may use notes/books/revision guides/the internet to help you.
Molecules X and Y are both hydrocarbons. X has
the formula C3H8 and Y has the formula C100H202.
DESCRIBE how you would expect their physical
properties to differ and EXPLAIN why they are
so different.
A material made from molecule Y is likely to be stronger than a material made from molecule X because each molecule is made up of more atoms. It will also have a higher melting point, because the gravitational bonds between the atoms in molecule Y because there are more of them.
ReplyDeletethe physical differences you would expect the separate hydrocarbons to have are dependent on the amount of hydrogen and carbon withheld in them. You would generally expect molecule X to be shorter than molecule Y as molecule Y has more atoms in. We know this through the stated formula's. Molecule X had 3 carbon atoms and 8 hydrogen atoms whereas molecule Y has 100 carbon atoms and 202 hydrogen atoms. This would then lead to properties between them to differ, such as molecule Y will have a higher boiling point as there is more matter to heat up meaning an increased amount of energy is required. When boiled a larger quantity of hydrogen gas and carbon dioxide would be released into the atmosphere which contributes to climate change. Molecule Y would also have a larger volume and surface area than molecule X as the length of the hydrocarbon is longer due to the differing amounts of hydrogen and carbon atoms.
ReplyDeleteAlthough molecule X and Y are made of the same elements (hydrogen and carbon) it is the physical molecular structure of them which makes them different.
ReplyDeleteMolecule Y is a lot longer than molecule X. Therefore I would expect molecule X to have a much lower melting and boiling point than molecule Y. This can be expected because the longer the hydrocarbon chain the greater the bonds between each polymer would be, because they have a greater surface area, and therefore more energy is needed to break them apart. This would result in long chains needing more heat energy to break the bonds between them, and therefore a higher melting point. This is true for molecule Y and because the molecule is so long it is most likely going to be solid at room temperature. However in the case of molecule X the melting point would be very low and it is very likely to be a gas at room temperature. This is because the molecule are very short small, and therefore it has a smaller surface area per molecule in relation molecule Y. Therefore the bonds would be weaker and less energy would be needed to break the molecule apart and this would result in a lower melting and boiling point.
Molecule's X and Y would also have other differences. Molecule X would be much more reactive than molecule Y and therefore it would also be more volatile and dangerous. Molecule X would be more reactive because it has a large surface area in proportion to its mass, therefore more surface area can come into contact with other molecules in order to react, hence it is more reactive. Molecule Y being a much larger molecule has a smaller surface area in relation to its mass, and therefore less of the molecule can come into contact with other substances, hence making it less reactive, and less dangerous as a result.
So to conclude, molecule X would have a lower melting and boiling point and be more reactive for the reasons explained above, and molecule Y would be less reactive and have a higher melting and boiling point. Molecule X would probably be a gas at room temperature whilst molecule Y is most like to be a solid.
I would expect molecule Y to be a lot heavier than molecule X, causing it to be stronger, denser, yet possibly more brittle due to the amount of atoms in its make-up and the forces attracting them together. However, they could have similar reactivity as they are both made from the same atoms, although different numbers of them. They are so different due to their different structures and the size due to the amount of atoms that make up each molecule, possibly causing the atoms to form different bonds (ionic or covalent) therefore affecting the properties of the molecule, such as its melting point.
ReplyDeleteMolecule X and molecule Y are very different from each other in quite a few ways. One way in which they are differnt is that Molecule Y has a much higher boiling point that X. As we can see from the formular it has a lot of elements in it, which means that these long molecules get tangled or knotted very easily. This gives the molecule a higher boiling point because more heat is needed to separate and untangle the molecules. In shorter molecules such us molecule X it is shorter in length meaning that it takes less heat and energy to sparate them. You could also expect molecule Y to be the stronger of the two becuase again, more energy is needed to separate the molecules so it therefore lasts for a considerably longer amount of time.
ReplyDeleteMolecule X aka Propane gas is a hydrocarbon and molecule Y aka Decacontane is also a hydrocarbon. Decacontane would have the larger melting point due to it having tighter bonds which would take more energy to brake down into a liquid state and the opposite is true of Propane. The state of both at room tempurature would be completely differant. For example the Propane would be in a gas state because it has a low melting point and is at the top of the fractional distalator where as the Decacontane
ReplyDeletewould be in a very soild state due to it having a very high melting point.
Molecule Y is longer than molecule X so it will have stronger bonds. This sugggests that it will be a solid with a high melting point.
ReplyDeleteThe physical properties will be different because hydrocarbons with only a few carbon atoms, like molecule x, are always gases, and have low boiling points whereas large hydrocarbons with many carbon atoms, like molecule y, are always solids and will have a high boiling point. This is because there are more bonds to break on molecule y than molecule x meaning that molecule x will be a liquid at room temperature because it doesn’t take much energy to separate the bonds. The fact that molecule y has more bonds is the reason why it is a solid at room temperature and has a higher boiling point.
ReplyDeleteI would expect Y to have a higher boiling point than X because the bigger the hydrocarbon is, the higher it's boiling point is.
ReplyDeleteIf X and Y were polymers, Y would be significantly longer than X because it would have more chemical bonds.
Y would be a lot more flammable than X because the molecule has more hydrogen.
C100H202 would have a much higher melting point than C3H8 as it has more bonds which would take much longer to heat up. Also i would expect that C100H202 would be alot thicker than C3H8 because of the amount of bonds and atoms it is made up off increasing the density and thickness. They are so different because C3H8 is a low density gas and C100H202,decacontane, is much dense.
ReplyDeleteMolecule Y would have a higher boiling point than molecule X. This is because it has more atoms, meaning it has more bonds. The more bonds a molecule has, the more energy is needed to break them, resulting in a higher boiling point. Molecule Y in liquid state would have a thicker viscosity than molecule X in liquid state. This is because molecule X is smaller than molecule Y, meaning it can move around more freely.
ReplyDeleteMolecule X and Y are very different hydrocarbons. Molecule X is a gas at room temperature, and small alkanes. This means that the chains are short and will have lower boiling points than other hydrocarbons. They have a lower boiling point because there are less intermolecular forces to break during chemical reactions. The light weight gas boils at -43C. Molecule Y is a solid at room temperature. The chains are longer and therefore the molecule has a higher melting point. This is because there are more intermolecular forces to break out of a solid form to a gas. The intermolecular forces of attraction are much stronger between big molecules than they are between small molecules. This solid boils at 600C. Molecule X is better for making fuel compared to Y because it is volatile, easily ignited and flows easily, whereas molecule Y is thick and sticky. When refining the hydrocarbons molecule X will be used for refinery gas due to its short chains, whereas molecule Y could be used for bitumen.
ReplyDeleteSince hydrocarbon X has a low number of carbon atoms in it, there would be an expectation of it being in gas form. This is because natrually, hydrocarbon compounds with a low amount of carbon and hydrogen atoms take the form of gases such as methane (CH4) or propane (which is actually hydrocarbon X). However hydrocarbon Y would be expected to be either a solid or a liquid with a higher melting and boiling point because it is a much bigger compound, therefore having a larger(much larger) molecular structure. Since all of the hydrogen and carbon atoms are linked this would mean that it has more solid properties unlike hydrocarbon X which is a small molecular structure therefore being light and being able to take the form of a gas. Some names for C100H202 can apparently be hectane,decacontane or n-Hectan.
ReplyDeleteMolecule X has 3 carbon molecules and 8 hydrogen molecules. However molecule Y has 100 carbon molecules and 202 hydrogen molecules. Due to the higher levels of atoms the density and bonds are that much stronger. Because the bonds are stronger it means that the boiling point of molecule Y will be higher. Equally the same reasoning is logical to apply towards the melting point. These higher levels are because of the stronger unity between molecules. Thus it requires more energy to be broken/boiled/melt.
ReplyDeleteYou would expect their physical properties to differ as C100H202 would be a longer chain and have more bonds than C3H8. C100H202 is used in plastic as it is stronger as there are more bonds. Also you would expect C100H202 to have a higher melting point as there are more bonds to break while C3H8 will have a lower melting point as there are less bonds. C3H8 and C100H202 are different as C100H202 has more carbon and hydrogen molecules making it stronger and the melting and boiling points different.
ReplyDeleteAlthough Propane (C3H8) and Hectane (C100H202) are both hydrocarbons they differ majorly. This is due to their molecular structure, where Propane has only three carbons Hectane have 100; in addition to this, Propane has eight hydrogens to Hectane’s two hundred and two. This means that Propane would be a considerably shorter molecule than Hectane. They also have dissimilar boiling points, this is because of the higher number of carbon atoms that Hectane has compared to Propane, therefore meaning that it would take more energy to heat it. Hectane is also a stronger molecule because of the amount of carbon – hydrogen bonds that it holds, compared to weak Propane.
ReplyDeleteIn turn this concludes that C8H8 and C100H202 differ due to the amount of carbon and hydrogen atoms that they hold, making their abilities (boiling points, strength, flexibility and physical appearance) diverse from one another.
x will be much shorter in length compared to y it will also have a tougher bond in it the y. y will have a longer length chain bit than x as it conatain more chemical's also x has water while y only has carbon and hydrogen. i thinnk???
ReplyDeleteMolecule Y has the formula C100H2O2 and Molecule X has the formula C3H8. This means that molecule Y is denser than molecule X. This also means that molecule Y has a higher melting point than molecule X. This is all because molecule Y has more atoms than molecule X. And if you melted both molecules, molecule Y would be thicker because there are more atoms.
ReplyDeleteyou would expect the hydrocarbon C3H8 to have a lower melting point, and possibly to be a gas at 0^C With C100H202, it should certainly be a solid at 0^C, due to the length of the hydrocarbon being a lot longer than the C3H8. The C100H202 will need to be heated up to a much higher temperature in order to separate due to the chemical bonds being much stronger.
ReplyDeletelevel 3 Lauren well done, however the huge amount of information wasnt really needed :P
ReplyDeleteTarget: make it more concise
Maja- Very good I'd probably give you 4 marks (Level 2) Because you understand the links between the two molecules, but to improve you could talk about intermolecular forces :)
ReplyDeleteMolly- I'd give you 3 marks (Level 2) because you know what you're talking about and but to improve, you could go into more detail and talk about intermolecule forces :)
ReplyDeletelevel 1/2 Jacob, you really needed more information and less grammmar mistakes....
ReplyDelete:D
molecule x would have a lower melting and boiling point than molecule y because it contains less atoms, which means that there would be less inter-molecular force, which would make it easier to break apart than molecule y.
ReplyDeleteY would have a higher melting and boiling point than molecule x. This is because Y has a longer polymer chain, which means that more energy is needed to break the chains due to higher amounts of intermolecular bonds.
ReplyDeleteYou would expect molecule Y to have a higher melting point because it has more intermolecular forces as it has more atoms. You would also expect molecule Y to be gloopy as it has more intermolecular forces causing it to need more energy to separate the atoms.
ReplyDelete