Answer: 104 g
Explanation: reaction Cr2O3 + 3 H2 ⇒ 2 Cr + 3 H2O
M(Cr2O3) = 150 g/mol, so n = m/M = 1.0 mol
Number of moles of H2 should be 3.0 moles and
It is much greater (150 g / 2.016 g/mol)
1 mol Cr2O3 produces 2 mol Cr.
Mass m= 2.0 mol· 52g/mol= 104 g
Answer:
D
Explanation:
but I am not sure about the answer
<span>What is the relationship between the atomic numbers and ionic radii of the elements in group 1? What is the relationship between atomic numbers and first ionization energies?
</span>Answer:
When we see down the groups, the atomic number and the atomic radius both increase.Extra shells are produced which increase the size of the higher atoms.
If we go across the periods, the atomic radius decreases due to the higher nuclear charge in the atoms. This pulls the electrons more closer to the nucleus.
Answer: This option is incorrect: <span>B. Covalent compounds are held together by much stronger interparticle forces than are ionic compounds.
Justification:
Ionic bonds, held by ionic compounds, are much stronger than covalent bonds, held by covalent compounds.
In ionic bonds one element yields one or more electrons forming a cation (a positively charged ion) and the other element accepts the electrons forming an anion (a negatively charged ion).
The anion and the cation are electrostatically atracted by each other. This electrostatic atraction force, named ionic bond, is very strong.
As result of this, the ionic compounds form strong crystals with high boiling and fusion points. A good example of this the sodium chloride, formed by the union of cation Na(+) and anion Cl(-).
The covalent bonds are result of sharing electrons and do not form ions. This bond is weaker than the ionic bond.
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