General Chemistry Answers

Write the steps in the complete ionization of the following polyprotic acids.

A. H2CO3

B. H3BO3

A certain concentration method works best when the analyte’s concentration is approximately 10 ppb.

a.) if method requires a sample of 0.5 mL, about what mass of analyte is being measured?

b.) if the analyte is present at 10% w/v, how would you prepare the sample for analysis?

c.) Repeat for the case where the analyte is present at 10% w/w.

d.) Based on your answers to part (a)-(c), comment on the method’s suitability for the determination of major analyte?

if 18.8 ml of 1.25 m sodium hydroxide solution is necessary to neutralize 25.0 ml of hydrochloric acid solution to a phenolphthalein end point, calculate the molarity of the hydrochloric acid solution

Predict whether the entropy change of the system in each of the following is positive or negative.1. O2(g) → 2O(g)2. N2 (g, 10 atm) → N2 (g, 1atm)3. 6CO2(g) + 6H2O(g) → C6H12O6(g) + 6O2(g)4. 2 H2 (g) + O2 (g) → 2 H2O (l)5. NH4Cl (s) → NH3(g) + HCl (g)

Given the reaction:

2 NaOH + H₂SO₄ ⟶

  Na₂SO₄ + 2 H₂O 

How many moles of sodium sulfate (Na₂SO₄) reproduced when 9.9 moles of sodium hydroxide (NaOH) are reacted with excess sulfuric acid?

For the following reaction, 108 grams of silver nitrate are allowed to react with 23.6 grams of copper .

silver nitrate(aq) + copper(s)  copper(II) nitrate(aq) + silver(s)

What is the maximum amount of copper(II) nitrate that can be formed?  grams

What is the FORMULA for the limiting reagent?

What amount of the excess reagent remains after the reaction is complete?  grams

calculate the time required to deposit 56g of silver from a silver nitrate(AgNO3)solution using a current of 4.5amper

For the following reaction, 4.41 grams of hydrogen gas are allowed to react with 39.8 grams of iodine .

hydrogen(g) + iodine(s)  hydrogen iodide(g)

What is the maximum mass of hydrogen iodide that can be formed?  grams

What is the FORMULA for the limiting reagent?

What mass of the excess reagent remains after the reaction is complete?  grams

calculate the new freezing point of water when 72.0 g of BaCl2 are added to 0.175 kg of water

Calculate the mole fraction of solute in the aqueous solution of 13% C₂H₅OH.