Answer:
Indeed, the two samples should contain about the same number of gas particles. However, the molar mass of 
is larger than that of 
(by a factor of about 
.) Therefore, the mass of the sample is significantly larger than that of the sample.
Explanation:
The and the sample here are under the same pressure and temperature, and have the same volume. Indeed, if both gases are ideal, then by Avogadro's Law, the two samples would contain the same number of gas particles ( and molecules, respectively.) That is:
.
Note that the mass of a gas 
is different from the number of gas particles 
in it. In particular, if all particles in this gas have a molar mass of 
, then:
.
In other words,
.
.
The ratio between the mass of the and that of the sample would be:
.
Since by Avogadro's Law:
.
Look up relative atomic mass data on a modern periodic table:
Therefore:
.
.
Verify whether 
:
- Left-hand side:
. - Right-hand side:
.
Note that the mass of the sample comes with only two significant figures. The two sides of this equations would indeed be equal if both values are rounded to two significant figures.
Answer:
1) Ca: [Ar]4s²
2) Pm: [Xe]6s²4f⁵
Explanation:
1) Ca:
Its atomic number is 20. So it has 20 protons and 20 electrons.
Since it is in the row (period) 4 the noble gas before it is Ar, and the electron configuration is that of Argon whose atomic number is 18.
So, you have two more electrons (20 - 18 = 2) to distribute.
Those two electrons go the the orbital 4s.
Finally, the electron configuration is [Ar] 4s².
2) Pm
The atomic number of Pm is 61, so it has 61 protons and 61 electrons.
Pm is in the row (period) 6. So, the noble gas before Pm is Xe.
The atomic number of Xe is 54.
Therefore, you have to distribute 61 - 54 = 7 electrons on the orbitals 6s and 4f.
The resultant distribution for Pm is: [Xe]6s² 4f⁵.
Answer:
=C₄H₄O₂
Explanation:
Given the empirical formula of a molecule, the he the quotient of the molecular mas and and the empirical mass=constant.
84.0 g/mol/mass of(C₂H₂O)=constant
=84/(12×2+1×2×16)
=84/42
=2
Therefore, the molecular formula is (C₂H₂O)₂=C₄H₄O₂
Answer:
The five phases of matter. There are four natural states of matter: Solids, liquids, gases and plasma. The fifth state is the man-made Bose-Einstein condensates. In a solid, particles are packed tightly together so they don't move much.
Answer:
Destiny = 5 g/ml
Explanation:
The formula for density is d=
Knowing this, divide your mass by volume:
10 g / 2 ml = 5 g/ml
Final answer:
Destiny = 5 g/ml
:
.
:
.