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echem
Questions (9)
Whats the name for HI(aq)?
I thought it was Hydrogen Iodide, but that's incorrect, does the aq change the name?
1 answer
1,151 views
If a cube with edges of 1.000 cm weighs 25.68 g, what would the mass of a cube
of the same material with sides 2.66 cm in length
2 answers
467 views
Consider three charged particles placed along the x-axis. The particle with q1 = 9.27 nC is at x = 7.66 m and q2 = 4.82 nC is at
2 answers
1,035 views
Two identical objects each hold a net charge of q = 8e. If the gravitational force between the two objects exactly cancels the
4 answers
3,077 views
Are 5s and 5p considered to be degenerate orbitals? I know degenerate orbitals mean that they have the same energy but different
1 answer
1,220 views
What's the highest occupied molecular orbital of I-?
I'm really confused here, I thought you could only find for the first two
0 answers
417 views
Which molecule based on the following enthalpies is the most stable?
Molecule A: -70 kJ/mol Molecule B: 100 kJ/mol Molecule C:
1 answer
643 views
If a sample of BaSO3 is found to contain 1.73 · 1018 SO32- ions how many moles of Ba2+ ions are present? Express your answer in
7 answers
867 views
An 0.6600 mol sample of an ionic compound has a mass of 131.9 g. Determine the mass (g) of one formula unit of the compound.
I
7 answers
1,162 views
Answers (17)
Doing chem lab hw too huh? 1.60x 10^-5 M * 0.1 L / 1.54E-04 M = L convert to mL
26,320 got it using a calculator
What are you trying to solve for?
Thank You!
Thank you! I should have known that, guess its getting late :)
That's interesting...because the altitude is so high you have to deal with escape velocity instead of the usual kinematics.
Oh, you mean the 'e' in the 8e might stand for 8 times electron charge of 1.60217646E-19 coulombs? I was doing it as 8 times e(the mathematical constant 2.71828183)
First need to convert km/hr to meters/second (I got around 3333.33 m/s but you might want to double check that) so 3333.33 is your initial velocity v_i using kinematics equation: v_f=V_i+at y=v_i*t+(1/2)at^(2) the highest point the projectile reaches is
c. use kinematics equation y=vi*t+1/2at^2 vi= 0 (because rock was dropped) a=-9.8m/s^2 t= 4s (time given) plug in and you get your height a. use kinematics equation vf^2=vi^2+2ay vi=0 (rock dropped) a=-9.8 y= (whatever you got from part c) plug in and
You have to make an equation and plug in the information based off what you are given. Perimeter= 2(W)+2(L) [1st equation] and they told us the Length= 29+w [2nd equation] so plug that into the first equation P=2W+2(29+W) 150=2W+2(29+W) solve for W(width)
Thank you for you help. I appreciate it!
Is it because in the first problem they gave you ions and in the second they gave you moles?
hmm okay. So when do you know if your suppose to divide by Avogadro's number as you did in the first problem or multiply by the ratio as you just did?
Oh I see...I was making it complicated So if the ratio wasn't 1 to 1 like in the following.. Na2SO3 is found to contain 2.37 · 10-3 mol of Na+ ions then I would have to use dimensional analysis to solve?
oh i got it!! (9.656/0.4200)/(6.022E-23)= 3.810E-23 so I do the same thing for the other problem! Thank you for you help :)
I get 199.848 but I'm pretty sure its suppose to be a small number... Here's a similar problem that I have the answer to but I don't know how to do... An 0.4200 mol sample of a metal has a mass of 9.656 g. Determine the mass (g) of one atom of the element.
131.9 g * (0.66mol)/(6.022*10^23) =1.4455*10^(-22)formula unit I don't think that's right....
