General Chemistry Answers

Dichlorodifluoromethane, CCl2F2, a refrigerant, is prepared from the reaction of CCl4 and HF.

CCl4 + 2HF → CCl2F2 + 2HCl

What will happen when 3.00 grams of CCl4 reacts with 3.00 grams of HF?

Which is the limiting reagent?

How much of the excess reagent remains unreacted?

How many grams of CCl2F2 was produced?

What will happen when 3.00 grams of CCl4 reacts with 3.00 grams of HF?

22. 2.76 g of silver carbonate on being heated yields a reduce weigh

a) 2.32 g b) 3.32 g c) 1.36 g d) 0.32 g 

II. The percentages of aqueous sugar solutions with different concentrations which are separated by a semipermeable membrane are given below. For each of the solutions below, indicate the direction of the flow of water in osmosis.

2% sugar

  5% sugar

  20%  sugar

  9% sugar

  1% sugar

  7% sugar

  5% sugar

  20% sugar

The vehicle that was transporting the dynamite sticks in Part A has been struck by another vehicle. A small fire appears to be spreading from a tire on a vehicle at the scene of the accident. Identify the explosive material that could be involved, and describe the chemical interaction that could be occurring as a result of the collision between the two vehicles. What immediate action should the EHS and FS responders take to protect human health and the environment?

I.

                                   3NaOH(aq) + 3FeCl₃                          NaCl (aq) + 3Fe(OH)₃ (s)

1. What mass of 3Fe(OH)₃ would be produced if 250 mL of 0.250M NaOH were added to a solution containing excess FeCl₃?

2. What volume of 2M NaOH will react with 4.0 g of FeCl₃?

3. What is the concentration of 20.50 mL of NaOH if this was neutralized with 20.0 mL of 0.150 M HCl in the reaction:

NaOH + HCl                       NaCl + HOH

D. A solution of propylene glycol (antifreeze) in the car’s radiator has a freezing point of -20°C. What is the molality of the solution?

E. The boiling point of an aqueous solution is 102.5°C. What is the freezing point of the solution?

Calculate the boiling point and freezing point of the following solutions:

1. 0. 575 molal aqueous solution

2. 1o g of C₆ H₁₂ O₆ dissolved in 259 g water

3. 0.5 mole Br₂ dissolved in 507 g chloroform

At a certain temperature, the 𝐾

p

 for the decomposition of H

2

S

 is 0.709.

H

2

S(g)↽−

−⇀

H

2

(g)+S(g)

Initially, only H

2

S

 is present at a pressure of 0.159 atm

 in a closed container. What is the total pressure in the container at equilibrium?

At equilibrium, the concentrations in this system were found to be[N

2

]=[O

2

]=0.200 M

and[NO]=0.500 M.

N

2

(g)+O

2

(g)↽−

−⇀

2NO(g)

If more NO

 is added, bringing its concentration to 0.800 M,

 what will the final concentration of NO

 be after equilibrium is re‑established?