What is the molecular formula for High Density Polyethylene?
It is C2H4, the same as with low-density polyethylene. If you need the heat of combustion with N2O, then the crucial datum that you need is the heat of combustion of HDPE with oxygen.
Chemistry Question - Please Help! Sorry, but I'm having trouble?
. For the standardization of the NaOH solution in Part A.7, the endpoint was consistently reproduced to a dark pink color. using too much NaOH, gives you a NaOH calculated strength that's too weak However, the endpoint for the titration of the acid solution in Part B.2 was consistently reproduced to a faint pink color. if you used the NaOH above to find the strength of that HCl... using a strength of NaOH that is too weak.... calculates out as fewer moles of NaOH needed calculates out as fewer moles of HCl present calculates out as a HCl with a strength that is too weak ============================== 2. In determining the percent acetic acid in vinegar, the mass of each vinegar sample is measured rather than the volume. Explain. because the label strength on the bottle is listed a 5% by weight, so we measure weights also b. If the vinegar were measured volumetrically (e.g., a pipet), what additional piece of data would be needed to complete the calculations for the experiment? we need the density of the vinegar to convert the ml's used into grams used ================================== 3. A drop of NaOH titrant, dispensed from the buret, adheres to the wall of the Erlenmeyer flask but is not washed into the vinegar with the wash bottle. Does this error in technique result in the reported percent of acetic acid being too high, too low, or unaffected? Explain had the drop fallen in... we would have seen that too much NaOH was used, for it would be too dark using too much NaOH leads us to believe that the vinegar was stronger the reported percent of acetic acid being too high
Which liquid would have a higher viscosity...?
The methanol is 0.618728 and Ethylene is 10.037064 of viscosity. Data Analysis * Viscosity has dimensions of mass x length-1 x time-1 It is usually expressed as force x time per area. One unit that has the correct dimensions is the poise. The viscosity of water at 25 ºC is 0.0089 poise, or 0.89 centipoise. * Use the following relationship to determine the viscosity of each liquid by comparing its properties to those of water: vis (liq) = {density(liq) x time(liquid) x vis(water)} / {density(water) x time(water)} Where: vis (liq) = viscosity of sample density (liq) = density of sample time(liquid) = flow time for sample vis(water) = viscosity of water = 0.89 centipoise (25 ºC) density(water) = density of water = 1 g/mL time(water) = flow time for water sample name density (g/mL) time (sec) calculated viscosity water 1.00 12.5 0.89 methanol 0.79 11 ethylene glycol 1.11 127
In chemistry is a high molar volume most correlated with low density, low reactivity, or the metallic elements?
A high molar volume means you've got a lot of volume for not very many moles. That's low density. [It says nothing about reactivity. Metallic elements mostly have low molar volumes, because they have high densities.]
Why does the substance with low intermolecular force has high vapor pressure?
It is the intermolecular force between molecules that holds the liquid particles together preventing them from becoming a vapor. The boiling point is defined as the temperature at which the vapor pressure equals the atmospheric pressure. If the intermolecular force is strong then the vapor pressure will be less because the molecules hold on to each other with greater force. Water, H2O, has much stronger intermolecular forces than hydrogen sulfide, H2S. So even though the molecular mass of H2S is about twice that of water, the boiling point of water is much higher than that of H2S because of higher intermolecular forces. Note, water has hydrogen bonding and H2S does not. A lower intermolecular force means that the molecules are able to escape into the vapor phase much easier than for those molecules with high intermolecular forces. The link below will guide you to a greater understanding of intermolecular forces that I can provide here.
Explain the relationship between specific heat and the heat capacity of a substance?
Specific heat capacity, also known simply as specific heat, is the measure of the heat energy required to increase the temperature of a unit quantity of a substance by a certain temperature interval. The term originated primarily through the work of Scottish physicist Joseph Black who conducted various heat measurements and used the phrase “capacity for heat.”[1] More heat energy is required to increase the temperature of a substance with high specific heat capacity than one with low specific heat capacity. For instance, eight times the heat energy is required to increase the temperature of an ingot of magnesium as is required for a lead ingot of the same mass. The specific heat of virtually any substance can be measured, including chemical elements, compounds, alloys, solutions, and composites. The symbols for specific heat capacity are either C or c depending on how the quantity of a substance is measured (see Symbols and standards below for usage rules). In the measurement of physical properties, the term “specific” means the measure is a bulk property (an intensive property), wherein the quantity of substance must be specified. For example, the heat energy required to raise water’s temperature one kelvin (equal to one Celsius degree) is 4.184 joules per gram—the gram being the specified quantity. Scientifically, this measure would be expressed as c = 4.184 J g–1 K–1. more here: http://en.wikipedia.org/wiki/Heat_capacity#Heat_capacity
Why does pressure increase when volume decreases?
You have a lousy teacher. The reason is that as volume increases, gas molecules are more likely to bump into each other and also to bump into the walls of the container. The term pressure, on a very small level, merely means the number of times that gas molecules hit the container walls, and how hard they hit the walls (which is affected by temperature, because higher temperature means the gas molecules have higher energy). Here are three laws to know: Boyle's law: P1V1 = P2V2 Where P1 is the original pressure, P2 is the pressure after you change it, V1 is the original volume, and V2 is the volume after you change it. This law shows that as volume decreases, pressure increases. Boyle's law shows a mathematical relationship between pressure and volume. Charles's Law: P1T2 = P2T1 Where P is pressure, and T is temperature. Charles's law shows that pressure increases mean temperature increases. It shows a mathematical relationship between pressure and temperature. Put them together, and you get the Combined Gas Law: P1V1T2 = P2V2T1 Which shows how pressure, temperature, and volume are all interconnected. I hope this helps.