General Chemistry Answers

An aqueous solution of HF is added to an aqueous solution of K(OH) and a reaction occurs. The

concentration of H + ions is 2.68x10 -1 M. Calculate the concentration of the (OH) - ions. Is the solution

more acidic or basic?

An aqueous solution of H 2 (CO 3 ) is added to an aqueous solution of Li(OH) and a reaction occurs. The

concentration of (OH) - is 3.75x10 -5 M. Calculate the concentration of the H 3 O +1 ions. Is the solution

more acidic or basic?

An aqueous solution of HCl is added to an aqueous solution of Na(OH) and a reaction occurs. The

concentration of H + ions in the solution is 1.0x10 -5 M, calculate the concentration of the OH –1 ions. Is the

solution more acidic or basic?

III-Please determine the type of chemical bonding of each compound

9.          Al(OH)₃                     

10.         AgCl               

11.         S₂Cl₂                    

12.         XeF₄                             

13.         NaSO₄                     

14.         CF₄                               

15.         PBr₃                             

A carnot engine operated between two temperature reservoirs mainted at 493.15K and 298.15K, respectively. If the desired output of the engine is 20.00kW, find the heat transfer to the low temperature reservior

How many grams of glucose (C6 H12 O6) are needed to prepare 800.0 g of a 5.0% glucose solution?

Thiocyanic acid (HSCN) has a pK_a of 4.0.

In what form would it exist in a solution of pH 0.0?

Calculate the standard entropy changes for the following reactions at 25°C:

a) H2(g) + CuO(s) → Cu(s) + H2O(g)

b) 2Al(s) + 3ZnO(s) → Al2O3(s) + 3Zn(s)

c) CH4(g) + 2O2(g) → CO2(g) + 2H2O(l)

d) S(s) + O2(g) → SO2(g)

e) MgCO3(s) → MgO(s) + CO2(g)

A blood sample contains 0.040 g glucose (C₆H₁₂O₆) per 100.0 mL. What is the molarity of glucose in this sample?

Performance Task #5: Saving Chemistry

Below is the enhanced text of chemistry set problems gathered from the notes of Antoine Laurent Lavoisier during the accident. Please do your best to help by answering the problems and showing your solutions.

I- Part : Concept of Mole

1.      A chemist has a jar containing 388.2 g of iron filings. How many moles of iron does the jar contain?

2.      A student needs 0.366 mol of zinc for a reaction. What mass of zinc in grams should the student obtain?

3.      Calculate the mass of aluminum that would have the same number of atoms as 6.35 g of cadmium.

4.      The weight of a diamond is given in carats. One carat is equivalent to 200. mg. A pure diamond is made up entirely of carbon atoms. How many carbon atoms make up a 1.00 carat diamond?

5.      Precious metals are commonly measured in troy ounces. A troy ounce is equivalent to 31.1 g. How many moles are in a troy ounce of gold? How many moles are in a troy ounce of platinum? of silver?