SarahF275

Most popular questions and responses by SarahF275
  1. Chemistry

    The question reads, "A spaceship is found to have a tiny leak that allows the effusion of air into space. Air in the spaceship is a mixture of nitrogen (N2), oxygen (O2), argon (Ar), and trace amounts of other gases. Predict how the percentages of the

    asked on December 15, 2017
  2. Chemistry

    In terms of its structure and intermolecular forces, why is neoprene able to stretch? I want to say it's because its carbons form a long chain which easily stretches, but I'm not sure how intermolecular forces factor into that. Thanks!

    asked on December 13, 2017
  3. Chemistry

    'Is the amphoteric substance C2O4H- more likely to act as an acid or a base, and why?' I was given the Ka of C2O4H- as 6.4 x 10^-5, so I calculated its pKa as about 4.19. Then I found its pKb as about 9.80, which makes its Kb about 1.56 x 10^-10. Thus, I

    asked on February 21, 2018
  4. Chemistry

    The problem states, 'A student wants to determine how long it takes to dissolve 51.3 g of common table salt (sodium chloride) in 1L of water by monitoring the solution. It takes 26.7 seconds for the salt to completely dissolve. Determine the rate of

    asked on March 5, 2018
  5. Chemistry

    'What is the pH of 0.083 M C5H5N if the Kb value for C5H5N is 2.9 x 10^-9?' I wrote the equation as C5H5N + H2O --> C5H6N^+ + OH^-. Then, I set up Kb = ([C5H6N^+][OH^-])/[C5H5N] Next I substituted the numbers in: (2.9 x 10^-9) = (x^2)/0.083 , which makes x

    asked on February 27, 2018
  6. Chemistry

    Will the ratio of the rates of effusion for two gases be the same as the ratio of the rates of diffusion for the two gases be the same? As I understand it, Graham's law applies to both effusion and diffusion, so the two ratios would be the same, right?

    asked on January 3, 2018
  7. Chemistry

    The equilibrium constant based on concentration is Kc = 190 for the reaction of carbon monoxide with hydrogen gas at 1000K. What can you infer about the relative rates of the forward and reverse reactions when the gases have the following concentrations at

    asked on January 29, 2018
  8. Chemistry

    'Describe the difference in intermolecular forces between 2-methyl-3-hexanone and 5-methyl-3-hexanol and how this affects the properties of the substances.' I'm looking at the molecles on Chemspider, and I want to say that because 5-methyl-3-hexanol has a

    asked on March 6, 2018
  9. Chemistry

    'Would the probability factor in the rate equation be greater or lower if the particles colliding were individual atoms instead of molecules? ' I want to say it would be lower because atoms have less kinetic energy than molecules due to their lesser mass,

    asked on January 20, 2018
  10. Chemistry

    'A solution is prepared by titrating a 100.0 mL sample of 0.10 M HF (Ka = 7.2 x 10^-4) with 0.1 M NaOH. What is the pH after 20.0 mL of the 0.10 M NaOH is added?' I'm a little bit confused but here's my ICE chart (in moles): HF________OH-_____F-

    asked on February 21, 2018
  11. Chemistry

    'Given 1.760 L of 0.384 M acid and 0.834 L of 0.724 base, find the final pH. Both the acid and base are strong.' First I multiplied the volume by the molarity to find the moles of each. Then I came up with this equation: HX + YOH --> H2O + YX (Y isn't

    asked on February 27, 2018
  12. Chemistry

    'Identify two factors that affect the change in entropy that occurs during the formation of an NaCl solution. State whether each factor causes an increase or decrease in entropy.' All I can think of is the dissolving process, which increases entropy, but

    asked on February 6, 2018
  13. Chemistry

    Quick question - I understand why ethanol is soluble in water, because it can form hydrogen bonds, but why is it also soluble in benzene, a nonpolar solvent?

    asked on January 4, 2018
  14. Chemistry

    I'm supposed to calculate the rate equation, including k, for the reaction whose data is given in the table: Experiment: 1 2 3 Initial Concentration X: 0.10, 0.10, 0.60 Initial Concentration Y: 0.20, 0.10, 0.10 Measured Initial Rate: 2.57, 1.25, 1.27 (I

    asked on January 8, 2018
  15. Chemistry

    How are absorbance and retention time related? Specifically, if something has a longer retention time, does that indicate high or low absorbance? I'm a little confused on how they're related. Thanks!

    asked on January 31, 2018
  1. Chemistry

    Quick clarification question - carbonyl groupts don't form hydrogen bonds, right? Since they don't have hydrogen attached to them, even though there's oxygen, they wouldn't participate in hydrogen bonding?

    posted on March 6, 2018
  2. Chemistry

    Unfortunately I don't know. The problem only calls them a strong base and a strong acid, so I assumed they were monoprotic.

    posted on February 27, 2018
  3. Math

    This is a parabola, and since they gave you the equation in vertex form, you can find the vertex, which will be at (-h, k). The vertex here, then, is at (4, 9). Since there's a negative sign out in front, we know this parabola opens down, meaning 9 is the

    posted on February 27, 2018
  4. Chemistry

    Just a quick question - why is the 0.82 cubed rather than the 0.83? Your equation matches mine, so wouldn't the concentration of hydrogen, the 0.83, be cubed? And then the concentration of water would be to the first power . . . ? I did this: (1.4 x 0.82)

    posted on January 29, 2018
  5. Chemistry

    So essentially, the order of X is 0 and the order of Y is 1? Which would mean k is equal to 12.85? That seems like a big k, but mathematically it fits.

    posted on January 9, 2018
  6. Chemistry

    Ahh never mind, I just remembered logarithms exist . . . oops

    posted on January 8, 2018
  7. Chemistry

    Ideal Gas Law: PV=nRT Convert temperature to Kelvin (C + 273) Once you've done that, you have 3/4 variables. Substitute them into the ideal gas law along with the appropriate gas constant value to get n, the number of moles. From there, use the molar mass

    posted on January 8, 2018