Answer:
Explanation:
K₂CrO₄ + ( COONa )₂ + 2BaCl₂ = Ba CrO₄ + ( COO ) ₂ Ba + 2 KCl + 2 NaCl
.033 M .053 M
Ksp of Ba CrO₄ is 2.10×10⁻¹⁰
Ksp of ( COO ) ₂ Ba is 1.30×10⁻⁶
A ) Ksp of Ba CrO₄ is less so it will precipitate out first .
B) Ksp = 2.10×10⁻¹⁰
Ba CrO₄ = Ba⁺² + CrO₄⁻²
C .033
C x .033 = 2.10×10⁻¹⁰
C = 63.63 x 10⁻¹⁰ M
Ba⁺² must be present in concentration = 63.63 x 10⁻¹⁰ M
C)
90% of precipitation of barium oxalate
concentration of oxalate to precipitate out = .9 x .0532 = .04788
( COO ) ₂ Ba = (COO)₂⁻² + Ba⁺²
.04788 M C
C x .04788 = 1.30×10⁻⁶
C = 27.15 x 10⁻⁶ M .
Answer:
Potassium
Explanation:
From the given riddle. Potassium is the right answer. This because on the periodic table, potassium has the smallest atomic number of any element in its period with the electronic configuration 1s2 2s2 2p6 3s2 3p6 4s1, it has the largest atomic radius within its group because the radius has no d-electron shell filled. Potassium is a soft metal but contains high reactivity.
You can tell that a crystal is a crystal if it creates a rainbow prism effect. Or you can tell by tapping the crystal. If he crystal makes a musical ring noise (like how a glass cup would sound) it’s a crystal.
Answer:
The atomic radius of krypton is similar to that of bromine. However, the effective nuclear charge of krypton is greater than that of bromine.
Explanation:
Ionizing an atom require moving an electron from the electron cloud of the atom to a point infinitely far away from the atom. The first ionization energy of this atom is the energy change in this process.
The electron and the nucleus are oppositely-charged. There is an electrostatic force between the two. Removing the electron requires overcoming this attraction. The size of the energy input depends on the electrostatic potential energy of the electron (the gravitational potential energy is much smaller than the electrostatic potential energy.) The separation between the electron and the nucleus is much larger than their radii. Both objects can be considered as point charges. Coulomb's Law gives the electrostatic potential energy of the two point charge that are close to each other.
,
where
is Coulomb's constant,
and
are the two charges, and
is the separation between the two charges.
Krypton and bromine are right next to each other in the same period. Their atomic radii will be similar to each other. The separation
between the outermost electron and the nucleus will also be similar for the two elements.
The first charge
can be the electron. However, data show that for elements after helium, the second charge
is smaller than the sum of charges on all protons in the nucleus. It turns out that the inner shell electrons (all of which are also negative) repel electrons in the outermost valence shell. The effective nuclear charge
of a neutral atom is <em>approximately</em> the same as the number of protons minus the number of non-valence electrons. That number will be slightly larger for krypton than for bromine. As a result, the electrostatic potential energy on a 4p (the outermost orbital for both Kr and Br) electron of krypton will be more negative than that on a 4p electron in bromine. Removing that electron will take more energy in Kr than in Br. The first ionization energy of Kr is hence greater than that of Br.
Answer:
One gram helium gas is equal to the 4.002602 g/mole
Explanation:
Helium gas is a gas or chemical element. The symbol of helium gas is He and the atomic number of this gas is 2. This gas is colorless, odorless, and tasteless. It is a non-toxic gas. It is found in the periodic table in the first place.
Helium is a very lightest gas and very abundant in nature in the universe. It is present in the universe around 24 percent. Helium is also called by another name that titan of sun. This is detected by the yellow line. The liquid form of helium gas is called cryogenics. This helium gas is used in lifting balloons and airplanes.