Other Chemistry Answers

 1.25 x 1022 atoms Cl

A sample of propane occupies 250.0 L at 125 kPa and 38°C. Find its volume at 100.0 kPa and 95°C. 

Calculate the freezing and boiling point of a solution containing 5.57 g of sodium chloride (NaCl) and 65.0 g of water. (MM of NaCl = 58.44 g/mol, K_f of water = 1.86˚C/m, K_b of water = 0.52˚C/m)

Comment “Fatty acids are storage fuels”. The weight of a person ABC is 65 kg. About 11.5 kg of his weight is due to the fat deposits in the body. He went for a hunger strike. Can you explain how long he can survive? i. without water and food? ii. without food but with water? 

0.236 moles of ammonium chloride

Comment “Fatty acids are storage fuels”. The weight of a person ABC is 65 kg. About 11.5 kg of his weight is due to the fat deposits in the body. He went for a hunger strike. Can you explain how long he can survive? i. without water and food? ii. without food but with water? 

A 37.98 g solid sample of mercury is heated from -39 ^oC its melting point, completely melted then heated to 106 ^oC, How much energy was absorbed by the sample? (Answer in kJ)

S=0.14 J/g^oC Delta H_f = 0.011 kJ/g

Lesson 17

N_2(g) + O_2(g) ————-> 2NO_(g)

2NO_(g) + O_2(g) ————-> NO_2(g)

3NO_2(g) + H₂O ——-> 2HNO_3(aq) + NO_(g)

Prepare a written response to the following question

1. An action plan is a strategy that compiles a series of well thought out steps that can be taken to accomplish a goal. Action plans are used at all levels of government; they are used by community organizations and they are also used on an individual level. Nitrogen oxides are factors in both acid rain and smog formation. A reduction in nitrogen oxides is needed. Research and formulate a personal action plan that you could follow to help cut down on emissions of this dangerous gas. Your answer should be well organized into paragraphs explaining in detail at least 4 actions that could be taken to reduce nitrogen oxide emissions.

Lesson 17 Nitrogen, a common pollutant from the combustion of auto fuels, produces several oxides. Assume that nitrogen dioxide is the most common oxide formed.

Common reactions of nitrogen in the atmosphere:

N_2(g) + O_2(g) ————-> 2NO_(g)

2NO_(g) + O_2(g) ————-> NO_2(g)

3NO_2(g) + H₂O ——-> 2HNO_3(aq) + NO_(g)

Prepare a written response to the following questions:

1. How does nitrogen dioxide contribute to the creation of acid precipitation if it undergoes similar transformation steps as sulphur dioxide?
2. Choose one of the above reactions, and demonstrate that a redox reaction is also occurring in the process of creating acid rain. Do this by writing the balanced half-reactions.

Lesson 16 1.Zinc reacts with hydrochloric acid based on the following equation:

Zn + 2HCl = ZnCl2 + H2

If 150 g of Zn reacts with 73 g of HCl:

a. Which reactant is the limiting reagent?

b. What mass of ZnCl₂ would be produced?

2.If 10.00 g of magnesium is reacted with 95.75 g of copper (II) sulphate, magnesium sulphate and copper are formed.

Mg + CuSO4 = MgSO4 + Cu

a. Which reactant is in excess?

b. Calculate the mass of copper formed.

3.Metallic silver can be prepared by the reaction of hydrogen gas with silver oxide.

Ag2O + H2 = 2Ag + H2O

Silver oxide is a very expensive reactant compared to hydrogen gas. If you were to carry out this reaction in the lab in the most cost effective way to produce a high yield, which of the reactants should be used in excess?