The formula of the ppt. formed is PbSo4 , which is inslouble.
The thermochemical equation is the chemical equation including the net change of enthalpy (heat).
The chemical equation for the decomposition of methanol to form methane and oxygen is:
2CH3OH --> 2CH4 + O2
The thermochemical equation is:
2CH3OH ---> 2CH4 + O2 - 252.8 kJ
Note that the heat is placed as negative at the right side because it is absorbed during the decomposition, so the environment will have 252.8 kJ less per each mole of O2 produced.
You can equivalently write:
2CH3OH + 252.8 kJ --> 2CH4 + O2
Answer:
36.55kJ/mol
Explanation:
The heat of solution is the change in heat when the KNO3 dissolves in water:
KNO3(aq) → K+(aq) + NO3-(aq)
As the temperature decreases, the reaction is endothermic and the molar heat of solution is positive.
To solve the molar heat we need to find the moles of KNO3 dissolved and the change in heat as follows:
<em>Moles KNO3 -Molar mass: 101.1032g/mol-</em>
10.6g * (1mol/101.1032g) = 0.1048 moles KNO3
<em>Change in heat:</em>
q = m*S*ΔT
<em>Where q is heat in J,</em>
<em>m is the mass of the solution: 10.6g + 251.0g = 261.6g</em>
S is specififc heat of solution: 4.184J/g°C -Assuming is the same than pure water-
And ΔT is change in temperature: 25°C - 21.5°C = 3.5°C
q = 261.6g*4.184J/g°C*3.5°C
q = 3830.87J
<em>Molar heat of solution:</em>
3830.87J/0.1048 moles KNO3 =
36554J/mol =
<h3>36.55kJ/mol</h3>
<em />
Answer:
2.8 g/mL is the density of the mineral.
Explanation:
The mass,
Volume of the object = Volume of water level rose - Initial volume of water = 30.5 mL - 20.3 mL = 10.2 mL
The expression for the calculation of density is shown below as:-
<u>2.8 g/mL is the density of the mineral.</u>
Assume 1 liter = 1 kilogram of water = 1000 grams of water.
Part A)
MW of hydrogen is 1.008g/mol, and oxygen is 16.00g/mol.
Find the MW of water by
2*(1.008) + (16.00) = 18.016g/mol.
Convert 1000g H2O to moles :
(1000g H2O)*(1mol H2O / 18.016g H2O) = 55.51 mol
Part B)
Using the answer from part A and Avogadro's number:
(55.51mol)*(6.022*10^23) =
3.343*10^25 molecules.
Hope this is helpful