General Chemistry Answers

the chemical reaction above releases about 2200 kJ of energy. How much energy is released when 2 miles of A^3 B^8 combusts

A solution which has a pH of 5.calculate [OH] And POH

2h2o2(g)→2h2o(g)+o2(g) what will decrease the equilibrium amount of H2O

What is He on the periodic table?

1. What is the pH of a 0.34 M solution of (weak acid) HF if the Ka = 6.8x10-4

?

2. If the pH of a weak acid solution is 9.5 and the original concentration of base was 0.30 M

A. what is the pOH?

B. what is the concentration of OH-

?

C. what is the equilibrium concentration of the base?

D. what is the Kb of the base?

3. Find the pH of a 0.325 M (weak acid) acetic acid solution. Ka = 1.8 x 10-5

.

4. Find the pH of a 0.056 M (weak acid)propionic acid solution (Ka = 1.4 x 10-5

).

5. Find the pH of a 0.075 M solution of (weak acid) formic acid. The acid dissociation

constant (Ka) for formic acid is 1.8 x 10-4

.

6. Find the pH of a 0.15 M solution of (weak base) ammonia, NH3. Kb = 1.8 X 10-5

7. Find the pH of a 0.600 M solution of (weak base) methylamine CH3NH2. Kb = 4.4 x 10–4

.

8. If the pH of (weak acid) HC3H5O2 is 4.2 and the Ka = 1.34x10-5

A. what is the equilibrium concentration of HC3H5O2?

B. what was the initial concentration of HC3H5O before dissociation?

A sample is observed to exert a pressure of 600 torr when confirmed to a 10.0 L vessels at 27 . C what will bbe its pressure in kPa when the gas is transfereed to an 8.0 L vessels at 300K?

The initial moles of a concentrated solution is 0.35mol. After dilution it final concentration is0.004mol/dm3. Calculate the final volume

During the practical class you used 1.0 ml of 30% w/w hydrogen peroxide in your experiment in a final volume of 3 ml of the reaction mixture. 

The final concentration of hydrogen peroxide in the reaction mixture was [a] % w/v

Note: the density of 30% w/w hydrogen peroxide is 1.11 g/ml. Use the relationship: % (w/w) x density = % (w/v). Answer with two significant figures. Do not type units or symbols.

what is the H+ in a solution with a pH of 9.28

A coffee-cup calorimeter initially contains 125 g water at 24.2°C. Potassium bromide (10.5 g), also at 24.2°C, is added to the water, and after the KBr dissolves, the final temperature is 21.1°C. Calculate the enthalpy change for dissolving the salt in J/g and kJ/mol. Assume that the specific heat capacity of the solution is 4.18 J/g °C and that no heat is transferred to the surroundings or to the calorimeter.