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Which equation depicts the hydrogen phosphate ion (HPO 4 2–) behaving as a Brønsted –Lowry base in water?

Consider the reaction NH 3( aq) + H 2O( l) NH 4 +( aq) + OH –( aq). K b for NH 3 is 1.8  × 10 –5 at 25°C. What is Ka for the NH 4 + ion at 25°C? Note: Written work required Hint: Kw = 1.0 x 10-14

For a monoprotic acid titration, the _____ in a titration is the point where number of moles of a strong base added equals the number of moles of an acid initially present.

What is the pH at the equivalence point when a 25.0 mL sample of 0.200 M aqueous formic acid (HCO 2H) is titrated with 0.100 M aqueous potassium hydroxide? ( K a of HCO 2H = 1.8 × 10 –4) Note: Written work required Hint: Weak acid + strong base titration problem

I understand that failure to submit my written work to payned@atc.edu,  within 5 minutes of submitting this test, will result in a 0 score for any questions that required calculations. To receive full credit, I further understand that I must include any formulas used, replacement of variables with appropriate numerical data, and circled correct final result with appropriate units and number of significant figures. Write your initials in space below to acknowledge your understanding.

What is the hydronium-ion concentration of a 0.30 M solution of HCN ( Ka = 4.9  × 10 –10) at 25°C? Note: Written work required Hint: ICE table required

What is the equilibrium pH of an initially 0.69 M solution of the monoprotic acid benzoic acid at 25°C ( Ka =  )? Note: Written work required Hint: ICE table required

The pH of a solution at 25 °C in which [OH –] = 3.2 × 10 –5 M is _____. ( K w = 1.01 × 10 –14) Note: Written work required

INSTRUCTIONS: The following problems relate to identifying and evaluating inductive and deductive arguments. Select the best answer for each. If the Big Bang theory is correct, then the universe is billions of years old. And if the Big Bang theory is correct, then the universe was not created in six days. Thus, if the universe is billions of years old, then it was not created in six days.

Which of the following is the correct formula for the ionic compound formed between calcium and nitrate?