<em>Answer:</em>
- The atom have a full valence electron shell.
<em>Explanation:</em>
- My question is that why covalent bonds take place?
Every atoms tends to from bond with another atoms in order to get nearest electronic configuration of nobel gases. They become stable when their valence shell become complete. So when covelant bond forms between atoms, share electrons to each other and stabilize themselves.
Ionic and covalent bonds are both strong intermolecular forces. They are generally both crystalline in structure. But relatively speaking, ionic bonds are much stronger. As a consequence, they have inherent properties of higher boiling points, higher melting points, lower volatility, etc. Also, ionic bonds display conductive properties because they are strong electrolytes. <em>Thus, the answer is 5) higher melting points.</em>
1) Calculate the number of mols,n, of the substance
n = mass/ molar mass = 326.0 g / 58.45 g / mol = 5.577 moles
2) Calculate the molar heat of fusion as the total heat released by the sample divided by the number of moles
hf = heat released / n = 4325.8 cal / 5.577 moles = 775. 59 cal /mol
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.
