Molarity (M) = moles of the solute (mol) / Volume of the solution (L)
The molarity of the given KCl solution = 2.10 M
Volume of the given KCl solution = 85.0 mL
Hence,
2.10 M = Moles of KCl / 85.0 x 10⁻³ L
Moles of KCl = 2.10 M x 85.0 x 10⁻³ L
= 0.1785 mol
Moles (mol) = Mass (g) / Molar mass (g mol⁻¹)
Molar mass of KCl = 74.56 g mol⁻¹
Hence,
0.1785 mol = Mass of KCl / 74.56 g mol⁻¹
Mass of KCl = 0.1785 mol x 74.56 g mol⁻¹
= 13.30 g
Hence, mass of given KCl in 85.0 mL is 13.30 g.
You can use the formula triangle . You can find it on google.
Aluminium is overall more reactive because it can loose electrons easier and therefore in a displacement reaction can force electrons upon less reactive metals such as chromium
Answer:
2.56 grams of H₂S is needed to produce 18.00g of PbS if the H2S is reacted with an excess (unlimited) supply of Pb(CH₃COO)₂
Explanation:
The balanced reaction is:
Pb(CH₃COO)₂ + H₂S → 2 CH₃COOH + PbS
By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction) they react and produce:
- Pb(CH₃COO)₂: 1 mole
- H₂S: 1 mole
- CH₃COOH: 2 moles
- PbS: 1 mole
In this case, to know how many grams of H₂S are needed to produce 18.00 g of PbS, it is first necessary to know the molar mass of the compounds H₂S and PbS and then to know how much it reacts by stoichiometry. Being:
- H: 1 g/mole
- S: 32 g/mole
- Pb: 207 g/mole
The molar mass of the compounds are:
- H₂S: 2* 1 g/mole + 32 g/mole= 34 g/mole
- PbS: 207 g/mole + 32 g/mole= 239 g/mole
So, by stoichiometry they react and are produced:
- H₂S: 1 mole* 34 g/mole= 34 g
- PbS: 1 mole* 239 g/mole= 239 g
Then the following rule of three can be applied: if 239 grams of PbS are produced by stoichiometry from 34 grams of H₂S, 18 grams of PbS from how much mass of H₂S is produced?
mass of H₂S= 2.56 grams
<u><em>2.56 grams of H₂S is needed to produce 18.00g of PbS if the H2S is reacted with an excess (unlimited) supply of Pb(CH₃COO)₂</em></u>
Explanation:
Monodentate ligands are the ligands which bind through only one donor atom. Example: chloride ion.
Monodentate ligands are the ligands which bind through two donor atom. Example: ethylenediamine.
When ligands bond with transition metal ion, repulsion between electrons in ligands and electrons in d orbitals of metal ion takes place which raises energy of d orbitals which causes the light to fall in the visible region.
Coordination number is number of donor atoms attached to central ion in a coordination complex. Coordination number of the chromium(III) is usually 6 means that usually chromium(III) bond to 6 ligands and form an octahedral complex.