Other Chemistry Answers

2H+ (aq) + ClO- (aq) + 2I- (aq) → Cl- (aq) + I2 (aq) + H2O (l)          Equation 2

In equation 2 on the lab information sheet, what element is oxidized? What element is reduced? Justify using oxidation numbers. 

How would each of the following laboratory mistake affect the calculated value of the percent NaClO in the commercial bleach (too high, too low, no change)? Explain. a. In step 6, some of the iodine that formed sublimed from the solution

Procedure

1. Use a pipet bulb and a 5-mL transfer pipet to measure EXACTLY 5.00 mL of a commercial bleach solution into a 100-mL volumetric flask.
2. Dilute to the mark with distilled water, stopper, and mix well.
3. Weigh out approximately 2 g solid KI. This is a large excess over that which is needed.
4. Pipet EXACTLY 25.0 mL of the dilute bleach into an Erlenmeyer flask.
5. Add the solid KI and about 25 mL of distilled water. Swirl to dissolve the KI.
6. Working in a fume hood, add approximately 2 mL of 3 M HCl while stirring the solution. The solution should be dark yellow to red-brown from the presence of the I3- complex ions.
7. Fill the buret with 0.100 M sodium thiosulfate solution (this may have already been done for you). Record the initial buret reading and the solution molarity in the Data table.
8. Titrate with the standard 0.100 M sodium thiosulfate solution until the iodine color fades to light yellow.
9. Add one dropperful of starch solution. The blue color of the starch-iodine complex should appear.
10. Continue the titration until one drop of Na2S2O3 solution causes the blue color to disappear. Record the final buret reading in the Data Table.

2H+ (aq) + ClO- (aq) + 2I- (aq) → Cl- (aq) + I2 (aq) + H2O (l)       

what element is oxidized? What element is reduced? Justify using oxidation numbers.

Determine the limiting reactant.

info given:

Ba(OH)2 volume-50.0 mL and molarity-1.000 M.

HCl(aq) volume-50.00 mL and molarity-1.000 M.

Initial temperature: 20 degrees celsius   Final temperature: 26.81 degrees celsius

Calculate the initial number of moles of Ba(OH)2 and H2SO4 at the beginning of the reaction. Be sure to use the correct equation (from the Chem 11 solutions unit)

The formation of an ionic compound between magnesium and bromine would have which of the following chemical formulas?

Nickel-63 decays to produce Copper (Cu) by emitting a beta particle.

Select the correct nuclear equation.

How would Quartz react with hydrochloric acid? I know precious metals are refined through acids and dissolution, but what about using hydrochloric or nitric acid on quartz, would it react with the silicon dioxide and dissolve the quartz leaving behind the metals that arent affected by the acids?

When a 1.50 g sample of sucrose, C12H22O11 (s), is burned in a bomb calorimeter assembly, the temperature of the system rises from  21.40°C to 28.28°C. If the heat capacity of the calorimeter is 3.60 kJ/°C, a) Calculate the molar heat of combustion of sucrose, in kJ/mol.

b) Verify the claim of sugar producers that one teaspoon of sugar (about 4.8 g) contains only 19 Calories (food Calories).