1. The average osmotic pressure of blood is about 7 atm. Therefore,: a. the average blood pressure is about 7 atm b. " " pressure inside the body is about 7 atm above the external pressure c. a pressure of about 7 atm would be requiredd to prevent osmosis of blood is in contact with pure water across a semipermeable membrane d. all of the above are true.
2. What is teh Celsuis temperature of 100.0 g of chlorine gas in a 40.0L container at 800mm Hg?
1. C would be true. A normal blood pressure of "120/80" means 120 mm Hg systolic and 80 mm Hg diastolic, which is 0.16 atm and 0.11 atm, respectively. These pressures are due to the pumping action of the heart. A container of blood or a solution of similar concentration will not create a pressure of 7 atm against the wall of the container!
2. Just plug into PV = nRT and solve for T. n is the moles of Cl2 gas. If you use R = 0.0821 L atm / mol K, V has to be in liters and P has to be in atmospheres. T will be in Kelvins.
1. When 200mL of 0.150M of hydrochloric acid is added to 125mL of 0.175M Mg(OH)2, the resulting solution will be: a. acidic b. basic c. neutral d. it is impossible to tell from the information given
First write the balanced reaction. Then calculate the moles of each reactant (volume X molarity, write units) and determine if one is in excess (the other will be the limiting reactant). If HCl is in excess, the solution will be acidic after the reaction. If Mg(OH)2 is in excess, the solution will be basic after the reaction. If neither is in excess, the solution will be neutral after the reaction because no unreacted HCl or Mg(OH)2 will remain.
First write the balanced reaction 2HCl + Mg(OH)2-----------------> MgCl2 + 2HOH Moles of HCl Conversion 200ml= 0.2L =0.2L * 0.150mole/L = 0.03 moles
Moles of Mg(OH)2 Conversion 125 ml= 0.125L =0.125L * 0.175mole/L = 0.021875 moles Since HCl moles is greater than that of Mg(OH)2(0.021875moles) therefore, HCl is aciditic.
Correct on the reaction and the calculation of the moles, but since the reaction stoichiometry is not simply one to one, you need to determine which is the limiting reactant the same way you did before in another problem. Calculate the moles of one of the products such as MgCl2 based on mole of HCl and based on moles of Mg(OH)2. The reactant that gives the lesser moles of the product is the limiting reactant, and the reactant that gives the greater moles of the product is in excess amount, meaning some of it will be left over after the reaction. That's the one that determines whether the solution is acidic or basic after the reaction.
Right calculations, wrong conclusion! Mg(OH)2 is in excess amount since you get a greater amount of product with it. HCl is therefore the limiting reactant. All of the HCl reacts, but there is extra Mg(OH)2 that does not react since it is in excess. Since Mg(OH)2 is a base, the excess amount of it that remains after the reaction causes the solution to be basic.
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