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Stoichiometry

Gas Laws - Volume, Density, and Temperature

1.) The density of liquid nitrogen is 0.808 g/mL at -196 degrees Celsius. What volume of nitrogen gas at STP must be liquefied to make 10.0 L of liquid nitrogen? 2.) Calculate the volume occupied by 2.5 mol of an ideal gas at STP. 3.) A hydrocarbon (compound containing only hydrogen and carbon) was analyzed to be 85.7 mass per

Percent by mass composition

While chlorofluorocarbons (CFC) are compounds that seem incredibly useful in industry, they also seem to wreak havoc on the ozone layer. If CFC-211 has a percentage by mass of chlorine of 80.46% and carbon of 10.90%, the rest being fluorine, what is the likely formula for CFC-211?

Forces in gases and in deep space

1.) How much force is required to inflate a high pressure bicycle tire to 95 pounds per square inch (655 kPa) with a hand pump that has a plunger with an area of 5.0 cm^2? 2.) An object exerts a force of 500. N and sits on an area of 4.5m X 1.5m. Calculate the amount of pressure exerted by the object in torr. 3.) During your t

Chemicals and Temperature

1. How small a change temperature can be detect by touch? How could smaller changes in temperature be detected? 2. What would be expect to observe if KHCO3 reacted with HBr? What test would be performed to identify the product? 3. If a reaction called for a minimum of 0.5 moles of table sugar, C6H12O6, and there was only o

Questions of density and volume

In my lab I determined volumes for two unknown metals by two different methods (displacement in a liquid: V=9ml vs. calculation of all sides: V=8.83 cm3 V=5ml V=4.75 cm3 The volumes are not the same. Which do you believe to be more accurate? Why?

Density Comparison of Masses

1. The density of an uncooked egg is much less than that of a hard boiled egg. Would it make any difference in this demonstration if the egg was hard boiled? If yes, explain what you would see if the graduated cylinder contained: a) only water b) only salt water c) 1/2 water, 1/2 salt water 2. Would a comparison of a can (

Density of Metals

1. Which is more dense, lead or brass? How it can determine? 2. A sheet of metal has the dimensions 5mm, 25 cm, 55cm and its mass is 14.7kg. Using the densities of metals, can you definitely tell what metal this is? How?

Understanding molar concentrations/volume /equations

1. molar concentration of a liter solution of HCl that has 65 grams of HCl in it? 2. How many grams of NaCl are needed to make a molar solution of 2 liters? 3. How many grams of a glucose are in 1 liter of 10% mass/vloume glucose solns?

Density, Volume

1. Describe two different ways by which you could measure the volume of a small cube. 2. Which is more dense, lead or brass? 3. If the value occupied by a liquid 48mL and the density if 1.2g/mL, what is the mass of the liquid? 4. A recycling plant has chips of hight density poly(ethylene) (HDPE, d=0.92g.mL) used for pla

A solution containing 292 g of Mg(NO3)2 per liter

A solution containing 292 g of Mg(NO3)2 per liter has a density of 1.108 g/mL. The molality of the solution is a. 2.00 m b. 2.41 m c. 5.50 m d. 6.39 m (See attached file for full problem description)

Moles in a solution

Calculate the number of moles of aluminum in a solution containing 10 grams sample. a. 0.742 mole of Al atoms b. 0.371 mole of Al atoms c. 26.98 mole of Al atoms d. 0.121 mole of Al atoms

Molarity of a HCl Solution

Calculate the molarity of a solution prepared by dissolving 3.12 grams of gaseous HCL in enough water to make 26.8 mL solutions. a. 1.6 M HCL b. 0.8 M HCL c. 3.2M HCL d. 5.4 M HCL

Molar Mass of a Compound from Weight

One molecule of a compound weighs 2.03 E-22 g. Its molar mass is: a. 48 gram per mole b. 92.1 gram per mole c. 114 gram per mole d. 122 gram per mole

Volume of Methane

What volume is occupied by 19.6 gram of methane (CH4) at 27 degree Celsius and 1.59 atm? a. 1.71 L b. 18.9 L c. 27.7 L d. 303 L

Grams in a Solution

How many grams of NaCl are contained in 350 ml of a 0.25 M solution of sodium chloride? a. 41.7 gram b. 5.11 gram c. 14.6 gram d. 87.5 gram

Thermochemistry with Heat of Reactions and Standard Enthalpies

1. (Stoichiometry/Heats of Reactions) a. How many kilojoules of heat energy are released when a 63.4-g sample of magnesium metal is completely converted to magnesium oxide according to the equation below? b. How many grams of oxygen gas are used up during an enthalpy change of -292 kJ? 2 Mg(s) + O2(g) -> 2 MgO(s)

Atomic Weights - The Atomic Mass of N Relative to H

Ammonia is a gas with a characteristic pungent odor. it is sold as a water solution for use in household cleaning. The gas is a compound of nitrogen and hydrogen in the atomic ratio 1:3. A sample of ammonia contains 7.933 g N and 1.712 g H . What is the atomic mass of N relative to H?

Photosynthesis Reaction Questions

1) Photosynthesis is estimated to produce 339.99999 g (dry weight) of plant matter per square meter, 50% of which is carbon. Calculate the total number of grams of carbon "fixed" each year by 1000 square meters. 2) The photosynthetic reaction can be represented as: 6CO2 + 6H2O -> C6H12O6 + 6O2 Of the glucose produced, 40.0%

Concentration of sodium chloeide

What would would the steps to find the concentration of sodium chloride in the final solution if 24.34 mL of 0.113 M BaCl2 completely reacts and the total volume of the reaction is 110.4 mL, give the reaction: BaCl2(aq)+Na2SO4(aq)ds=BaSO4(s)+2NaCl(aq)

Ionic Equilibria

(See attached file for full problem description) --- 1. When blood is donated, sodium oxalate solution is used to precipitate Ca2+, which triggers clotting. A 104-mL sample of blood contains 9.7à?10-5 Ca2+/mL. A technologist treats the sample w/100.00 mL of .1550 M Na2C2O4. Calculate [Ca2+] after the treatment (Ksp of C

Calculating mass with Q=It

"Calculate the mass of chromium produced in 1.0 hour by the electrolysis of molten CrO3 with an electrical current of 15 A." The answer is 4.85 g, but I'm not entirely sure how to get there. Don't I need the reaction in order to know how many electrons are produced by the electrolysis? I think I first use Q = (I)(t) = (15)

Determining Density from Volume

I have a 40 lb container that measures 14x20x30 and need to find the density. I also have another 40 lb container that has a volume of 1.9 gal. How do you find the density for both to see which one is lighter?

Properties of solutions - Propylene Glycol

9) Calculate the mass of propylene glycol (C3H8O2) that must be added to 0.340 kg of water to reduce the vapor pressure by 2.88 torr at 40 °C. 10) Calculate the freezing point and boiling point of an antifreeze solution that is 50.0 % by mass of ethylene glycol (C2H6O2) in water. 11) Calculate the freezing point and boili

Simple explanation needed

10kg petrol is burned in a car engine. What two main chemicals come from the exhaust and how much of each in kilograms?