<h3>a) <u>Answer;</u></h3>
A- 7.30 M
<h3><u>Explanation;</u></h3>
3.65 Sodium sulfate
Na2(SO4) dissociates to give sodium ions and sulfate ions.
Na2(SO4) → 2Na+ + SO₄²₋
Therefore, twice the concentration of sodium ions as far as molarity is concerned.
<em><u>Concentration of sodium ions = 3.65 × 2= 7.3 M</u></em>
<h3>b) <u> Answer;</u></h3>
B- 2.76 M
<h3><u>Explanation;</u></h3>
b) 1.38 M sodium carbonate
Sodium carbonate dissociates completely to yield Sodium ions and carbonate ions
Na₂CO₃ → 2Na+ + CO₃²₋
The concentration of sodium ions will be twice the concentration of initial compound since it has a ratio of two.
<em>Concentration of sodium ions = 1.38 ×2 </em>
<em> = 2.76 M</em>
<h3>
c) <u>
Answer;</u></h3>
<em>0.785 M</em>
<h3><u>
Explanation;</u></h3>
b) 0.785 sodium bicarbonate
Sodium bicarbonate dissociates completely to sodium ions and a bicarbonate ions.
NaHCO₃ →Na+ + HCO₃⁻
In this case the concentration of Na+ will be equal to the concentration of the original compound since they share the same ratio.
Thus; <em><u>Na+ concentration = 0.785 M</u></em>
The answer is electrical energy
Answer:
Number 6 is correct all substances are made of molecules.
Explanation:
A molecule is a formation of atoms or a chemical and all substances are made of chemicals.
Answer:
Molarity is a unit that measures how much moles of solute dissolved in a liter of solvent. Molarity expressed using capital M while molarity, a different unit, expressed using lower case m.
We want to make 0.005 M solution which means we need 0.005 moles of KmnO4 per liter of water. First, we have to calculate how many grams of KMnO4 we need for the solution.
We want to make 250ml solution, so the number of moles of KMnO4 we need will be: 0.005 mol/liter *(250 ml * 1liter/1000ml)= 0.005 mol/liter * 1/4 liter = 0.00125 moles
The molecular mass of KMnO4 is 158g/mol, so the mass of KMnO4 we need will be: 0.00125 moles * 158g/mol= 0.1975 grams
We know that we need 0.1975 g of KMnO4, now we weigh them and put it inside a dish. After that, we prepare Erlenmeyer or a volumetric flask filled with water half of the volume needed(125ml). Pour the weighted solute into the flask, stir until all solute dissolved.
Then we add water to the container slowly until its volume reaches the 250ml mark.
Answer is: 127 <span>grams of metallic copper
</span>Chemical reaction: 2Al + 3CuSO₄ → Al₂(SO₄)₃ + 3Cu.
m(Al) = 54 g.
m(CuSO₄) = 319 g.
m(Cu) = ?
n(Al) = 54 g ÷ 27 g/mol
n(Al) = 2 mol.
n(CuSO₄) = 319 g ÷159,5 g/mol.
n(CuSO₄) = 2 mol, limiting reagens.
from reaction n(CuSO₄) : n(Cu) = 3 : 3 (1 : 1).
n(Cu) = 2 mol.
m(Cu) = 2 mol · 63,5 g/mol.
m(Cu) = 127 g.
