the oxidation state refers to the hypothetical charge on an atom when it is isolated from its neighboring atoms and it can be calculated as given below

-123456 1. What is the oxidation number of S in HSO, ? 2. What is the...
1. A system does 425 kJ of work and loses 125 kJ of heat to the surroundings. What is the change in internal enery of the system? a) 550 kJ c) -300 kJ e) OkJ b) 300 kJ d) - 550 kJ 2. How many grams of NaBr (102.89 g/mol) are contained in 250.0 mL of a 0.200 M solution of sodium bromide a) 50.0 g c) 5.14 g c) 0.0500 g b) 20.6 g d) 0.486 g 3. A...
A student mixes 41.0 mL of 2.84 M Pb(NO3)2(aq) with 20.0 mL of 0.00235 M Nal(aq). How many moles of Pbla(s) precipitate from the resulting solution? Number K,,[Pb12()] – 9810 mol What are the values of [Pb2+), [1]. [NO3-), and [Na*) after the solution has reached equilibrium at 25 °C? Number Number [Pb?*] = Number Number [no; ]- 0 M [nat)-
17. When 13.8 mL of 0.870 M lead(II) nitrate reacts with 90.0 mL of 0.777 M sodium chloride, 0.279 kJ of heat is released at constant pressure. What is AH for this reaction? Pb(NO3)2(aq) + 2NaCl(aq) → PbCl2(s) + 2NaNO3(aq) a. 23.3 kJ b. 4 kJ c. 1.84 kJ d. 3.41 kJ e. 8 kJ
The thermochemical equation for the reaction is shown below: 4 Al(s) + 3 O2(g) → 2 Al2O3(s) AH - -3352 kJ How much heat is released when 8.07 g of Al react with Oz(g) at 25 °C and 1 atm? -1.68 x 104 kJ 0-104 kJ 0-754 kJ 0-2.50 x 102 kJ Which of the following processes is exothermic? o Water condensing from steam. The vaporization of water The melting of ice. O Heating water to form steam Select the...
The thermochemical equation for the reaction is shown below: 4 Al(s) + 3 O2(g) → 2 Al2O3(s) ΔH = -3352 kJ How much heat is released when 8.07 g of Al react with O2(g) at 25 oC and 1 atm? Select the oxidation-reduction reaction(s)? 1. Cl2(g) + ZnBr2(aq) → ZnCl2(aq) + Br2(l) 2. Pb(ClO4)2(aq) + 2 KI(aq) → PbI2(s) + 2 KClO4(aq) 3. CaCO3(s) → CO2(g) + CaO(s) Select the strong acid in aqueous solution from the set below. Group...
Question 5 5 pts A 77.0-mL sample of a 0.203 M potassium sulfate solution is mixed with 55.0 mL of a 0.226 M lead(II) nitrate solution and this reaction occurs: K2SO4(aq) + Pb(NO3)2 (aq) - 2 KNO3(aq) + PbSO4(s) The solid PbSO4 is collected, dried, and found to have a mass of 2.62 g. Determine the percent yield. 1 mole PbSO4 = 303.26g 91.1% 120% 69.5% 80.1% Question 29 5pi If 1.85 g MgO is combined with enough 1.00 M...
Insoluble Li2Co3 (s) precipitates when solutions of Na2Co3 (aq) and LiCl (aq) are mixed. To measure the enthalpy change, 250. mL of 0.80 M Na2Co3 (aq) and 250. mL of 1.6 M LiCl (aq) are mixed in a coffee-cup calorimeter. The temperature of the mixture rises by 1.6 °C. Calculate the enthalpy change for the precipitation of Li2Co3 (s) in kJ/mol. (Assume the density of the solution is 1.0 g/mL, and its specific heat capacity is 4.2 J/g · K.)
2 Na3PO4(aq) + 3 Cu(NO3)2(aq) → Cu3(PO4)2(s) + 6 NaNO3(aq) What mass of Cu3(PO4)2 can be formed when 23.7 mL of a 0.790 M solution of Na3PO4 is mixed with 76.3 mL of a 0.730 M solution of Cu(NO3)2?
A 77.0-ml sample of a 0.203 M potassium sulfate solution is mixed with 55.0 mL of a 0.226 M lead(II) nitrate solution and this reaction occurs: K2SO4(aq) + Pb(NO3)2 (aq) + 2 KNO3(aq) + PbSO4(s) The solid PbSO4 is collected, dried, and found to have a mass of 3.71 g. Determine the percent yield. 1 mole PbSO4 = 303.26 g Hydrazine, N2H4, is a liquid used as a rocket fuel. It reacts with oxygen to yield nitrogen gas and water....
Question 1 2 pts Given the balanced chemical equation: Thermometer Ba(NO3)2(aq) + Na2SO4(aq) →BaSO4(s) + 2 NaNO3(aq) - Stirrer A 0.30 L of 0.15 M Ba(NO3)2(aq) is mixed with excess Na2SO4(aq) to make 200.0 g of solution in a coffee-cup calorimeter and allowed to react completely. The temperature of the solution rises from 23.5 °C to 24.9 °C. Answer the question in each step to find Hrxn for this reaction. Cs,soln = 4.18 J/g °C Cover Step 1: The reaction...