An: Calculate the molarity of a solution made by adding 120 g of NaOH (40.00 g/mol) to enough water to make 500.0 mL of solution. a) 4.0 M b) 6.0 M c) 1.0 ...
Explanation:
First we have to find Ka1 and Ka2
pKa1 = - log Ka1 so Ka1 = 0.059
pKa2 = - log Ka2 so Ka2 = 6.46 x 10⁻⁵
Looking at the values of equilibrium constants we can see that the first one is really big compared to second one. so, the pH will be affected mainly by the first ionization of the acid.
Oxalic acid is H₂C₂O₄
H₂C₂O₄ ⇄ H⁺ + HC₂O₄⁻
0.0356 M 0 0
0.0356 - x x x
Ka1 =
= x² / 0.0356 - x
x = 0.025 M
pH = - log [H⁺] = - log (0.025) = 1.6
Answer : If we list the given chemicals according to their increasing oxidising ability then the order will be like this; 1 being the strongest and 6 being the weakest
1. K > 2. Ca >3. Ni> 4. Cu> 5. Ag> 6.Au
Explanation : Considering the reduction potential of each chemical species it will be easy to identify their oxidising capacity and differentiate accordingly;
More negative the value of reduction potential more is the ability of the chemical species to get oxidised.
Chemicals with their reduction potential is given below.
K has -2.92; Ca has -2.76; Ni has -0.23; Cu has 0.52; Ag has 1.50 and Au has 1.50.
<span>Molecular compounds, which are represented by molecules, are usually made of non-metals only (or of metalloids and non-metals). Ionic compounds, which are represented by formula units, are made of metals and non-metals.
More detail if you're interested: Molecules and formula units are the representative particles for molecular and ionic compounds, respectively. By that I mean, one unit of a molecular compound is a molecule...a bundle of atoms covalently bonded that exists separately from all the other molecules. One unit of an ionic compound is a formula unit. A formula unit is a representation of the compound's formula. For example, the formula unit of NaCl is one Na^+1 ion and one Cl^-1 ion. The formula unit of AlCl3 is one Al^+3 ion and three Cl^-1 ions. Ionic compounds don't have separate bundles of atoms like molecular compounds do, so the formula unit is just the smallest number of ions that it takes to represent the formula. </span>
Chemical bonds hold atoms together to form compounds through the sharing of electrons or the transferring of electrons.
Bio is not my strongest subject, but I am pretty sure that a pyramid of numbers differs from an ecological pyramid because it displays the number of organisms at each trophic level