Answer:
P = 14.1 atm
Explanation:
Given data:
Mass of methane = 64 g
pressure exerted by water vapors = ?
Volume of engine = 24.0 L
Temperature = 515 K
Solution:
Chemical equation:
CH₄ + 2O₂ → CO₂ + 2H₂O + energy
Number of moles of methane:
Number of moles = mass / molar mass
number of moles = 64 g/ 16 g/mol
Number of moles = 4 mol
Now we will compare the moles of water vapors and methane.
CH₄ : H₂O
1 : 2
4 : 2/1×4 = 8 mol
Pressure of water vapors:
PV = nRT
R = general gas constant = 0.0821 atm.L/mol.K
P = 8 mol × 0.0821 atm.L/mol.K× 515 K / 24.0 L
P = 338.25 atm.L/ / 24.0 L
P = 14.1 atm
Trace fossils provide us with indirect evidence of life in the past, such as the footprints, tracks, burrows, borings, and feces left behind by animals, rather than the preserved remains of the body of the actual animal itself. so i would say B.
Answer:
Compass - Gps
Explanation:
I belive the pro's and cons are
GPS you are trusting a little man made device
the direction you to give you directions
are going on and that it won't break or die
a device not a paper map
Compass
You can see north east south and it is usually carefully crafted for o outdoors but it has no roads and
west on the compass and if given no directions, extremely
you can see the roads follow directions confusing until you learn it
like go south then east.
B. Most rocks are composed of single mineral
Answer:
Explanation:
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
As the size of atom increases the ionization energy from top to bottom also decreases because it becomes easier to remove the electron because of less nuclear attraction and as more electrons are added the outer electrons becomes more shielded and away from nucleus.
On left side of periodic table atoms of metals are more reactive by loosing the electrons or we can say metals are more reactive by loosing the electrons so their reactivity increase down the group because of easily removal of electrons.
On right side of periodic table atoms of nonmetals are more reactive by gaining the electrons. As we move down the group nuclear attraction becomes smaller because of shielding thus electron are less attracted by nucleus and reactivity decreases.