A 1.00 L buffer solution is 0.150 M CH3COOH (pKa = 4.74 ) and 0.200 M NaCH3COO. What is the pH of this buffer solution after 0.0500 mol KOH are added?
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Calculate the time of arrival of singly charged cations with masses 14, 15, 28, 32, 550, and 551, when the ions are accelerated with 10,000 V and distance to the detector is 1m
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With the aid of a simple schematic describe the principle of operation of a linear time of flight mass analyzer (LTOF).
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Which statements regarding weak bonds are true?
A) Represent the bonds that hold water molecules together in liquid state
B) Are what hold the three-dimensional structures of proteins, nuleic acis, and lipid membranes together
C) sre ofter electrostatic (Involving charges particles or regions) in natre
D A&B
E) A B & C
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If the mixing ratio of carbon dioxide is 404 ppmv and the number density of air is 2.69x1025 molecules m-3, determine the mass density.
Question 24 options: show work
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8 x 10-4 kg m-3 |
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4.7 x 10-3 kg m-3 |
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0.18 ppm |
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793 kg m-3 |
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Assuming that 1.00 L of 4% PVA solution is spread out to form a thin sheet of thickness equal to the average length of a PVA strand, calculate the total area of the liquid sheet. Then calculate the average of the sheet of solution per strand of PVA. Assuming this area is a little square, the square root of this area gives the edge length of the square which is approximately the average distance between the PVA strands. Show that this distance is about ten times the estimated diameter of a PVA strand (0.2-0.3 nm).
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why does cross linking affect solubility, melt viscosity, recyclability, modulus, and service temperture?
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What is the pH when 50 ml of 0.040 M NaOH is mixed with 50 ml of 0.040 M HN3 (Ka= 1.9*10^-5)
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Exactly 47.0 mL of 0.2 M HNO2 are titrated with a 0.2 M NaOH solution. What is the pH at the equivalence point ?
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Balance the following equation, remove all mole fractions
C5H12O + K2Cr2O7 + H2SO4 = Cr2(SO4)3 + C2H4O2 + K2SO4 + H2O
I need the half reaction 1, half reaction 2, and the complete balanced equation (with K+ and SO42-)
Please explain your steps, I'm trying to study for a test and I'm not sure how to go about this. Thank you!
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other than a counterfeit detection pen, how is chemistry being used in counterfeit money detection , and give details about preventative measures that involve application of chemistry
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The vapour pressures of acetone and benzene at 65oC are 580mmHg and 475mmHg respectively
if 5.8g of acetone is mixed with 15.6g of benzene what is the total vapour pressure at 65oC
Will this mixture distill at 65oC? Explain
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Please give answer and explanation !
Consider the following reaction: CH4 (g) + 2O2 (g)----------} CO2(g) + 2H20(g) ^Hr= -890 kj
a) is heat absorbed or evolved in the course of the reaction?
b) Calculate the amount of heat trasnferred when 45g of CH4 is decomposed by this reaction at constant pressure.
c) For the given sample of CH4 the enthalpy change on reaction is 66.8 kj. How many grams of H2O are produced?
d) what is the value of ^Hr for the reverse of the previous reaction? How many KJ of heat are released when 27g of H2O reacts completely with CO2to form CH4 and O2 at constant pressure?
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Calculate the pH for each case in the titration of 50.0 mL of 0.200 M HClO(aq)0.200 M HClO(aq) with 0.200 M KOH(aq).0.200 M KOH(aq). Use the ionization constant for HClO.HClO.
What is the pH before addition of any KOH?KOH?
pH=pH=
What is the pH after addition of 25.0 mL KOH?25.0 mL KOH?
pH=pH=
What is the pH after addition of 35.0 mL KOH?35.0 mL KOH?
pH=pH=
What is the pH after addition of 50.0 mL KOH?50.0 mL KOH?
pH=pH=
What is the pH after addition of 60.0 mL KOH?60.0 mL KOH?
pH=pH=
https://sites.google.com/site/chempendix/ionization
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