Q/A coal sample has 90% carbon, 3.3% hydrogen, 3% oxygen, 0.8%
nitrogen. 0.9% sulphur and 2%...
Q/A coal sample has 90% carbon, 3.3% hydrogen, 3% oxygen, 0.8%
nitrogen. 0.9% sulphur and 2% ash. For 50% excess air supply
determine percentage composition of dry flue gases by volume and
minimum oxygen required.
Make an estimate of the composition of carbon, hydrogen,
oxygen, and nitrogen in the dry mass of a bacterium. Using
knowledge of the size and mass of a bacterium, the fraction of that
mass that is "dry mass" (that is, ca. 30%) and the chemical
constituents of a cell, figure out the approximate small integers
(< 10) for the composition CmHnOpNq, that is, find m, n, p, and
q.
carbon, hydrogen, oxygen and nitrogen make up the bulk of the
atoms in the human body. However, there are many trace elements
present as well. Pick three of these trace elements and do a little
Internet research to find out where they're found and what they're
used for in the body.
A compound contains only carbon, hydrogen, nitrogen, and oxygen.
Combustion of 0.157g of the compound produced 0.213g CO2 and
0.0310g of H2O. In another experiment, 0.103g of the compound
produced 0.0230g of NH3. What is the emerical formula of the
compound? In a seperate experiment, the molar mass is found to be
454.3 g/mol. what is the molecular formula of the compound? hint:
assume that all carbon ends up in CO2 and all hydrogen ends up in
H2O.Also assume that...
A 38.40 mg sample of an organic acid composed of just carbon,
hydrogen, and oxygen was burned in pure oxygen to give 37.54 mg CO2
and 7.684 mg H2O in a combustion analysis. In a separate
experiment, the molecular mass was determined to be 90. In a
titration, 40.2 mg of the acid dissolved in 50 mL of water required
14.28 mL of 0.0625 M NaOH for complete neutralization. Use these
data to draw a reasonable Lewis structure for the...
A 33.153 mg sample of a chemical known to contain only carbon,
hydrogen, sulfur, and oxygen is put into a combustion analysis
apparatus, yielding 59.060 mg of carbon dioxide and 24.176 mg of
water. In another experiment, 21.223 mg of the compound is reacted
with excess oxygen to produce 9.1726 mg of sulfur dioxide. Add
subscripts below to correctly identify the empirical formula of
this compound (use this order of elements: CHSO)
Combustion analysis of a 0.2608 g sample of a compound
containing carbon, oxygen, and hydrogen only produced 0.5501 g of
carbon dioxide, and 0.2703 g of water.
Determine the empirical formula of this compound. If the molar
mass for this compound is 104.1 g/mole, find the molecular formula.
Write a complete balanced equation for the combustion reaction of
this compound.
A sample of air contains 78.08% nitrogen, 20.94% oxygen, 0.0500%
carbon dioxide, and 0.930% argon by volume. How many molecules of
each gas are present in 4.65 L of the sample at 49°C and 4.97 atm?
Enter your answers in scientific notation.
A sample of air contains 78.08% nitrogen, 20.94% oxygen, 0.0500%
carbon dioxide, and 0.930% argon by volume. How many molecules of
each gas are present in 6.62 L of the sample at 38°C and 2.21 atm?
Enter your answers in scientific notation.
× 10 molecules N2
× 10 molecules O2
× 10 molecules CO2
× 10 molecules Ar
A sample of air contains 78.08% nitrogen, 20.94% oxygen,
0.0500% carbon dioxide, and 0.930% argon by volume. How many
molecules of each gas are present in 5.12 L of the sample at 87°C
and 7.52 atm? Enter your answers in scientific
notation.
? = molecules N2
? = molecules O2
? = molecules CO2
? = molecules Ar
1. How many neutrons are there in oxygen? In hydrogen?
In nitrogen?
2. Distinguish between atoms and molecules and among
protons, neutrons, and electrons.
3. Compare and contrast covalent bonds and ionic
bonds.
4. Explain how polar covalent bonds allow hydrogen bonds
to form, and provide an example.
7. Define pH scale, acid, base, and buffer. How do
buffers reduce changes in pH when hydrogen ions or hydroxide ions
are added to a solution? Why is this phenomenon important in...