Answer:
ΔH = 2.68kJ/mol
Explanation:
The ΔH of dissolution of a reaction is defined as the heat produced per mole of reaction. We have 3.15 moles of the solid, to find the heat produced we need to use the equation:
q = m*S*ΔT
<em>Where q is heat of reaction in J,</em>
<em>m is the mass of the solution in g,</em>
<em>S is specific heat of the solution = 4.184J/g°C</em>
<em>ΔT is change in temperature = 11.21°C</em>
The mass of the solution is obtained from the volume and the density as follows:
150.0mL * (1.20g/mL) = 180.0g
Replacing:
q = 180.0g*4.184J/g°C*11.21°C
q = 8442J
q = 8.44kJ when 3.15 moles of the solid react.
The ΔH of the reaction is:
8.44kJ/3.15 mol
= 2.68kJ/mol
1.204 x 10 ( 24 ) atoms of magnesium are present.
In order to go from mass of magnesium there have to do 2 things
1. convert mass of Mg to moles of Mg using the molar mass of Mg as converted to a factor
2. convert moles of Mg to atoms of Mg using the Avogadro's number ( 6.02 x 10 (23) as a conversion factor
Hope my it helped a little :) <span />
Answer:
When a reduction reaction and an Oxidation reaction takes place due to passing of current through water the molecules of water split into the compounds. Where it is made up of hydrogen in its state of gas and also Oxygen in its state of gas this method is most vastly is known as electrolysis.
In this process a certain direct current is passed from inside water. This direct current value can be near about 1.23 voltages the reaction that happens inside is given below.
2 Water---> Oxygen + 4 hydrogen ions + 4 Electrons
2 Hydrogen ions + 2 electrons ----> hydrogen gas
If 1000 ml (1 L) of CH₃COOH contain 1.25 mol
let 250 ml of CH₃COOH contain x
⇒ x =
= 0.3125 mol
∴ moles of CH₃COOH in 250ml is 0.3125 mol
Now, Mass = mole × molar mass
= 0.3125 mol × [(12 × 2)+(16 × 2)+(1 × 4)] g/mol
= 18.75 g
∴ Mass of CH₃COOH present in a 250 mL cup of 1.25 mol/L solution of vinegar is <span>18.75 g</span>