Place 10 drops of zinc nitrate into A3 of the 24 well plate. 5. Place 10 drops of iron (III) chloride into A4 of the 24 well plate. 6. Place 10 drops of copper (II) sulfate into A5 of the 24 well plate.
: Se, calculated molar mass 78.93 g] 4) A 0.3528 gram mixture of H2SO4 (molar mass 98 grams) and H3PO4 (molar mass 98 grams) was mixed with a little water and titrated with 9.70 mL of 1.000 M NaOH: 3NaOH(aq) + H3PO4(aq) →3H2O(l) + Na3PO4(aq) 2NaOH(aq) + H2SO4(aq) →2H2O(l) + Na2SO4(aq) What was the percent by mass H2SO4 in the original mixture? [Ans. : 30.6] 5) A 0.9030 gram sample of Z(OH)2 and 20.00 mL of 2.000 M HCl were put into a 100.0 mL volumetric flask and mixed with enough extra water to make 100.0 mL of solution. A 10.00 mL aliquot of this solution was taken and titrated with 17.64 mL of 0.05121 M NaOH. What is the identity of the element Z?
Given that 11.40 cm3 of K2Cr2O7 was required for complete oxidation, a) Calculate the numbers of moles of Cr2O7- used. b) Calculate the number of moles of Sn2+ that react with Cl2. c) Calculate the concentration of Cl2 in bleach. 5. Pyrolusite is a manganese ore containing mainly manganese (IV) oxide, MnO2.
Name Date Sub Teacher Calcium The element Calcium on the peroidic table has the symbol of Ca. Calcium has an atomic number of 20. The atomic mass of Calcium is 40.078 amu. The melting point of calcium is 839.0* c - 1112.15 *k and the boiling point is 1484.0* c - 17757.15* k. The number of protons and electrons in Calcium is 20. The number of nuetrins is also 20 in Calcium.
Which compound has the greatest percentage by mass of Magnesium? a) MgCl2 : * MgCl2 = 24.31g + (2* 35.45g) = 95.21g Percentage by mass of Mg: * (24.31g/ 95.21g )* 100= 25.53 % b) Mg(NO3)2 : * Mg(NO3)2 = 24.31g + 2* (14.01g+(16.00g*3)) = 148.33g Percentage by mass of Mg: * ( 24.31g/ 148.33g) * 100 = 16.39% c) Mg3(PO4)2 : * Mg3(PO4)2 = (24.31g *3) + 2( 30.97g + (16.00g * 4)) = 262.87g Percentage by mass of Mg: * ( 72.93g/ 262.87g) * 100 = 27.74% d) MgSO4 : * MgSO4 = 24.31g + 32.07g + (16.00g * 4) = 120.38g Percentage by mass of Mg: * (24.31g/ 120.38g) * 100 = 20.19% The compound has the greatest percentage by mass of Magnesium is Mg3(PO4)2 3. Magnesium sulfide is 43.1 % Mg by mass. How many tons of Sulfur can be produced by the thermal decomposition of 20.5 tons of magnesium sulfide? Lab 4 Objective: The goal of the experiment is to find the mass of
Initial Concentration Chemical Mass of Graduated Cylinder (g) Mass of Sugar (g) Molar Mass (g) Moles in Graduated Cylinder Total Volume (L) Molarity (mol/L) Sugar (C12H22O11) 16.6 10 342.29 .29 .1 .29 Data Table 9. Dilution Series Dilution Volume (mL) Mass (g) Density (g/mL) Initial Concentration (M) Volume Transferred (mL) Final Concentration (M) 0 25.0 mL 25 25 0 mL 0ml 1 25.0 mL 10 10 .29 2.5 mL 5.4M 2 25.0 mL 15 40 .435 4.5 mL 6.8M 3 25.0 mL 20 45 .58 3.0 mL 9.4M 4 25.0 mL 25 50 7.25 6.0 mL 11.2M Data Table 10. Molarity vs. Density Molarity vs. Density molarity is the concentration of a solution given in gram moles of solute per liter of solution. Density is the degree of compactness of a substance. Questions: How would you prepare 10 mL of a 0.25M HCl solution if 1M HCl was available?
Repeat the titration until there are two titres within 0.1cm3 of each other. Record results in a suitable table. Results: Rough Titre: 7.653 First Run: 6.553 Second Run: 6.453 Third Run: 6.553 Calculations: During the titration, iron(II) ions are oxidised to iron(III) ions and manganate(VII) ions are reduced to manganese(II) ions. The equation is as follows: 5Fe2+(aq) + MnO4-(aq) + 8H+(aq) ? 5Fe3+(aq) + Mn2+(aq) + 4H2O(l) The above equation shows that one mole of manganate(VII) ions reacts with 5 moles of iron(II) ions in acid solution.
How many kilograms of pure HCl would be used to make this hydrochloric acid? (Assume that 30% has two significant figures. There are 2000 lb/ton.) (Obj 15) 30 ton HCl 2000 lb 1 kg ? kg HCl = 6.0 × 105 ton HCl soln 100 ton HCl soln 1 ton 2.205 lb 30 ton HCl 2000 lb 453.6 g 1 kg ?
0.36 B. 2.3 C. 9.0 D. 11 (1) 3. What is ∆H for the reaction below in kJ? CS2(g) + 3O2(g) ® CO2(g) + 2SO2(g) [∆Hf / kJ mol–1: CS2(g) 110, CO2(g) – 390, SO2(g) – 290] A. −570 B.
| 6.99V | 0.14A | 7. | 8.00V | 0.16A | 8. | 9.03V | 0.18A | 9. | 9.98V | 0.20A | 10. | 18.01V | 0.36A | 50-ohm Resistor | V drop | I through | 1.