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CHEM HELP! The diprotic acid H2A has pK1 = 4.00 and pK2 = 8.00. (a) At what pH is [H2A] = [HA?]?
The diprotic acid H2A has pK1 = 4.00 and pK2 = 8.00. (a) At what pH is [H2A] = [HA?]? (b) At what pH is [HA?] = [A2?]? (c) Which is the principal species at pH 2.00: H2A, HA?, or A2?? (d) Which is the principal species at pH 6.00? (e) Which is the principal species at pH 10.00?
1 AnswerChemistry9 years agoCHEM HELP! Urgent please! Calculate the pH of an NaOCL solution that is 1.00 x 10^-2 M?
Calculate the pH of an NaOCL solution that is 1.00 x 10^-2 M
Please help and show work! THANK YOU!!
2 AnswersChemistry9 years agoPLEASE CHEM HELP with stronger acid or base?
Which is a stronger acid, (a) or (b)?
(a) Dichloroacetic acid Ka = 8 x 10^-2
(b) Chloroacetic acid Ka = 1.36 x 10^-3
Which is a stronger base, (c) or (d)?
(c) UREA Kb=1.5 x 10^-14
(d) Hydrazine Kb= 1.1 x 10^-6
1 AnswerChemistry9 years agoCHEM HELP!! PLZ Given the two reactions shown with their equilibrium constants,?
Given the two reactions shown with their equilibrium constants,
PCl3(g) + Cl2(g) PCl5(g) K1
2 NO(g) + Cl2(g) 2 NOCl(g) K2
What is the equilibrium constant for the reaction,
PCl5(g + 2 NO(g) PCl3(g) + 2 NOCl(g)
Question 4 options:
1) K1K2
2) K2/K1
3) K1/K2
4) (K1K2)-1
5) K2-K1
1 AnswerChemistry9 years agoGiven the reaction, 2 NO(g) + O2(g) 2 NO2(g), for which the enthalpy of reaction is -118.9 kJ. Which one of th?
Given the reaction, 2 NO(g) + O2(g) 2 NO2(g), for which the enthalpy of reaction is -118.9 kJ. Which one of the following actions will cause an increase in the equilibrium concentration of NO in a closed reaction chamber?
1) adding more O2(g) through an injection nozzle
2) increasing the temperature of the system
3) removing the NO2 from the system
4) increasing the pressure of the system while temperature is kept constant
5) adding a catalyst
1 AnswerChemistry9 years agoCHEM HELP!!! PLEASE! Calculate the pH of?
Calculate the pH of 1.0 x 10^-3 M HBr
Correct answer is 3.00 but please help me show the work to get that answer!! THANKS!
1 AnswerChemistry9 years agoHELP! Given that pKb for nitrite ion is 10.85, find the quotient in a solution of?
Given that pKb for nitrite ion(NO2^-) is 10.85, find the quotient[HNO2]/[NO2^-]in a solution of sodium nitrite at
(a) pH 2.00
(b) pH 10.00
( Hint:Use Henderson Hassebalch equation) pH = pKa + log ( [A^ -]/ [HA])
1 AnswerChemistry9 years agoCHEM HELP!! A buffer was prepared by dissolving 0.100 mol of the weak acid HA?
HELP WITH SHOWING WORK FOR CHEMISTRY!
A buffer was prepared by dissolving 0.100 mol of the weak acid HA (Ka = 1.00 × 10−5) plus 0.050 mol of its conjugate base Na+A− in 1.00 L.
Find the pH.
Correct Answer: 4.70
Hint : Use Henderson Hassebalch equation pH = pKa + log ( [A^ -]/ [HA])
3 AnswersChemistry9 years agoCHEM HELP PLZ! Find the pH and fraction of association?
NEED HELP SHOWING WORK PLEASE :)
Find the pH and fraction of association (α) of a 0.100 M solution of the weak base B with
Kb = 1.00 × 10−5. (use the exact equation(quadratic equation).
Correct Answer: 11.00, 0.995%
2 AnswersChemistry9 years agoFor the reaction 2A(g) + B(aq) + 3C(l) ⇌ D(s) + 3E(g), the concentrations at equilibrium are found to be A: 2?
For the reaction 2A(g) + B(aq) + 3C(l) ⇌ D(s) + 3E(g), the concentrations at equilibrium are found to be
A: 2.8 × 103 Pa
B: 1.2 × 10−2 M
C: 12.8 M
D: 16.5 M
E: 3.6 × 104 Torr
Find the numerical value of the equilibrium constant that would appear in a conventional table of equilibrium constants.
Please show me the work that does along with the answer.
THANKS!
1 AnswerChemistry9 years agoHELP!! In an experiment, 200.0 g of a pure solvent is found to have a freezing point of 16.66 degrees C?
In an experiment, 200.0 g of a pure solvent is found to have a freezing point of 16.66 C. Its freezing point depression constant is known to be 3.90C/m. Into this solvent, 16.92 g of an unknown is dissolved. (Assume that the compound is not ionic) The new freezing point of the solution is measured as 14.21 C.
a. What is the freezing point depression for the solution?
b. What is the molality (m) of the solution?
c. The molality represents the number of moles of solute (The unknown compound) per 1000 g of solvent. What is the number of moles for the 200.0 g of solvent that is present?
d. What is the molecular weight of the unknown compound (grams/mole)?
1 AnswerChemistry9 years agoIn the van der Waals equation of state for a real gas, the van der Waals constant, a, represents a correction?
In the van der Waals equation of state for a real gas, the van der Waals constant, a, represents a correction for
Question options:
1) a positive deviation in the measured value of P from that for an ideal gas due to the finite volume of space occupied by molecules of a real gas
2) a negative deviation in the measured value of P from that for an ideal gas due to the finite volume of space occupied by molecules of a real gas
3) a positive deviation in the measured value of P from that for an ideal gas due to the attractive forces between the molecules of a real gas
4) a negative deviation in the measured value of P from that for an ideal gas due to the attractive forces between the molecules of a real gas
5) a positive deviation in the measured value of P from that for an ideal gas due to the finite mass of the molecules of a real gas
2 AnswersChemistry9 years agoA gas sample occupies a volume of 1.264 L when the temperature is 168.0 °C and the pressure is 946.6 torr. How?
A gas sample occupies a volume of 1.264 L when the temperature is 168.0 °C and the pressure is 946.6 torr. How many molecules are in the sample?
Question 19 options:
1) 2.07 × 1022
2) 2.62 × 1022
3) 2.65 × 1023
4) 2.65 × 1024
5) 6.88 × 1022
1 AnswerWeather9 years agoFind an equation of a line passing through point (1/2,-2) that's perpendicular to the line given by 3x-2y=5?
So my teacher had wrote on my paper when I first turned it in that
3/2x-5/2 and to find a line perpendicular to this.
PLEASE SOMEONE HELP!!! GIVE ME THE ANSWER TO THIS :(
4 AnswersMathematics9 years agoSolve the inequality x> 1 + 1/x?
I got through most of this problem and my teacher said it was right. I need to get the final answer by solving so please help!!!
x^2 - x -1 / x > 0 The x^2 - x- 1 is all divided by the x. Please help!!!!
2 AnswersMathematics9 years agoSolve the inequality 3x-5/x-4 >(greater than OR EQUAL TO) 2?
My teacher had wrote to set it up like this
(3x-5)/x-4 - 2(x-4)/x-4 > (greater than or equal to) 0 (zero)
2 AnswersMathematics9 years agoFind two real numbers such that one is three less than twice the other and their product is as small as?
Find two real numbers such that one is three less than twice the other and their product is as small as possible.
3 AnswersMathematics9 years agoFind the equation of the line passing through the point (1/2, -2) that is perpendicular to the line given by?
Find the equation of the line passing through the point (1/2, -2) that is perpendicular to the line given by 3x-2y = 5
2 AnswersMathematics9 years ago