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Set up the integral to compute the length of the parabola  y = 4 x 2 + 3 {“version”:”1.1″,”math”:”y=4 x^2+3″}between the points (-2,19) and (3,39). Simplify the integrand, but do not evaluate the integral.

Balance the following equation. Enter just the number (no spaces or any other characters.). If the coefficient is 1 (one) enter the number 1 otherwise Canvas will mark it unanswered and you will lose the points. [a] HClO4   + [b]  P4O10 (g)  →  [c] H3PO4(g)  +  [d] Cl2O7

A coffee-cup calorimeter contains 100.0 mL of 1.000 M HCl (excess) at 20.3 °C. When 1.82 g Zn(s) is added, the temperature rises to 30.5 °C. What is the heat of reaction per mol Zn? Assume that the heat of solution is that of water, and the density of the HCl is 1.000 g/mL.  Zn(s)  + 2 HCl(aq)  → ZnCl2(aq)  + H2(g)   

Balance the following equation. Enter just the number (no spaces or any other characters.). If the coefficient is 1 (one) enter the number 1 otherwise Canvas will mark it unanswered and you will lose the points. [a] B2O3(s) (aq)   + [b]  HF(aq)  →  [c] BF3(aq)  +  [d] H2O(l)

Balance the following equation. Enter just the number (no spaces or any other characters.). If the coefficient is 1 (one) enter the number 1 otherwise Canvas will mark it unanswered and you will lose the points. [a] C7H9   + [b]  HNO3  →  [c] C7H6(NO2 ) 3  +  [d] H2O(g)

When 4.00 g of iron (MM = 55.845 g/mol) is reacted with 4.00 g of water (MM = 18.02 g/mol) according to the chemical equation shown below: What is the limiting reactant? What mass of Fe3O4(s) (MM = 231.53 g/mol) is produced? How many grams of the excess reactant are left? If 4.75 g of Fe3O4(s) were obtained, what is the percent yield? Must show your work on scratch paper to receive credit. 3 Fe(s) + 4 H2O(l) → Fe3O4(s) + 4 H2(g)

For many years, the extraction of gold (the separation of gold from other materials) involved the use of potassium cyanide according to the reaction: 4 Au(s)  + 8 KCN(aq)  + O2(g)  + 2 H2O(l)  → 4 KAu(CN)2(aq)  + 4 KOH­(aq) What is the minimum amount (in mL) of a 0.750 M KCN solution needed to extract 29.0g (about an ounce) of gold? Must show your work on scratch paper to receive credit.

Given the data:  Ca(s) + ½ O2(g) → CaO(s)  ΔH = −635.1 kJ CaCO3(s) → CaO(s) + CO2(g) ΔH = 178.3 kJ using Hess’s Law the ∆H for the reaction below is [a] kJ:2 Ca(s) + O2(g) + 2 CO2(g) →  2 CaCO3(s)Must show your work (scratch paper) to receive credit.

When 6.00 g of CS2 (MM = 76.13 g/mol) gas react with 10.0 g of Cl2 (MM = 70.90 g/mol) gas in the following reaction: CS2(g) + 3 Cl2(g) → CCl4(l) + S2Cl2(l) What is the limiting reactant? How many grams of CCl4 (153.81 g/mol) are produced? How many grams of the excess reactant are left? If 6.50 g of CCl4 are produced, what is the percent yield of the reaction? Must show your work on scratch paper to receive credit.

Based on the standard enthalpies of formation provided, calculate the ΔH°reaction for the reaction: C6H12(l) + 9 O2 (g) → 6 CO2(g) + 6 H2O(l)   ΔH°f (kJ/mol) C6H12(l) -151.9 CO2(g) -393.5 H2O(l) -285.8 Must show your work (scratch paper) to receive credit.