Answer to Question #11965 in Chemistry for Kelvin

Question #11965
6. What would be the mass of 0.50 moles of water?
7. What would be the volume of 100 moles of water? 7.96 moles
8. Which has more moles of water, 100 ml of water or 100 grams of water?
9. Do you think one mouthful of water is less than one mole, equal to one mole or more than one mole of water?
10. Fill your mouth with water, spit it into a measuring cup and estimate
the volume to the nearest ml.
11. Determine the correct number of moles of water in a mouthful of water. Compare this to your estimated
value.


Extension: You must show all steps clearly for credit.
(a) Calculate the percent by mass of each element (H and O) in water (H2O)
(b) Calculate the percent by mass of each element (C, H and O) in ethanol (C2H5OH)




Sodium Chloride

Required measurements and calculations: Record measurements clearly, with units. Show all calculations and clearly label your answers. Check your answers.

1. What is the molar mass of sodium chloride (NaCl)?
2. Look at the label on a container of salt. Record the mass (in grams) of salt in the container.
3. Is this amount in the sample less than one mole, equal to one mole or more than one mole of sodium chloride (NaCl)?
4. How many moles of sodium chloride (NaCl) are in the sample?
5. Look at a large bag of chips or other snack food for the mass of sodium. This represents 40% of the total mass of NaCl in the bag. Predict whether the bag contains less than one mole, equal to one mole or more than one mole of sodium chloride (NaCl).
6. Calculate the mass of NaCl in the bag by multiplying the mass of sodium by 2.5. Then divide that number by 1000 to convert from mg to grams.
7. Use the mass calculated in #6 to determine the correct number of moles of NaCl in the bag.

Extension:
(a) Calculate the percent by mass of each element (Na and Cl) in sodium chloride (NaCl). You must show all steps clearly for credit.
(b) Calculate the percent by mass of each element (Ca and Cl) in calcium chloride (CaCl2).
(c) Find the percent by mass of each element in aluminum chloride AlCl3.

Sidewalk Chalk


Required measurements and calculations: Copy these questions into your data book. Record measurements clearly, with units. Show all calculations and clearly label your answers. Check your answers.

1. What is the molar mass of chalk (calcium carbonate, CaCO3)?
2. The mass of your piece of chalk (calcium carbonate, CaCO3) is 25.0 grams. How many moles of chalk do you have to start?
3. You write your name on the sidewalk but don’t completely use up your piece of chalk.
4. The mass of your remaining chalk (calcium carbonate, CaCO3) is 10.0 grams. What mass of chalk was used in writing your name on the sidewalk?
5. Did you leave more than, equal to or less than one mole of chalk outside?
6. Calculate how many moles of chalk (calcium carbonate, CaCO3) you left outside on the sidewalk.

Extension: You must show all steps clearly for credit. (a) How many molecules of chalk (calcium carbonate, CaCO3) did you leave outside? (b) How many calcium (Ca) atoms did you leave outside? (c) How many carbon (C) atoms? (d) How many oxygen (O) atoms? (e) How many total atoms did you leave outside?

% Composition of Candium


Required measurements and calculations: Copy these questions into your data book. Show all calculations and clearly label your answers. Check your answers.

1. A sample of candium contains a mixture of 20 Skittles and 30 M&M’s. Assuming that each candy represents an atom and that your sample is the compound, write the formula for the compound candium using the smallest whole number ratio of Mm to Sk (MmxSky)
2. The mass of your sample is 41.0 grams.
3. The mass of the M & M’s in your sample is 21.0 grams.
4. Calculate the average mass of an M & M (the molar mass of Mm).
5. The mass of the Skittles in your sample is 20.0 grams.
6. Calculate the average mass of a Skittle (the molar mass of Sk).
7. Calculate the molar mass of candium using the formula determined in #1, the molar mass of Mm found in # 4 and the molar mass of Sk found in #6.
8. Calculate the % by mass of Mm in candium using this equation:

% by mass Mm = Molar mass Mm(#4) x number of Mm atoms in candium formula (#1) X 100
Molar mass of candium (#7)

9. Similarly, calculate the % by mass of Sk in candium.
1
Expert's answer
2012-07-17T08:36:56-0400
Unfortunately, your question requires a lot of work and cannot be done for free.
Submit it with all requirements as an assignment to our control panel and we'll assist you.

Need a fast expert's response?

Submit order

and get a quick answer at the best price

for any assignment or question with DETAILED EXPLANATIONS!

Comments

No comments. Be the first!

Leave a comment

LATEST TUTORIALS
APPROVED BY CLIENTS