Answer:
Ok, so the process here is to convert the mass of H2 (hydrogen gas) to moles by dividing the mass by the molar mass of H2. Once you have the moles then you have to multiply by the STP (standard temperature and pressure) molar volume which should be 22.4.
Molar mass of H2 = (1.01)x2 = 2.02g/mol
19.3/2.02 = 9.55 moles
Now just multiply the moles by the molar volume
9.55 moles x 22.4 = 213.92 Litres of H2 are in 19.3g of H2
Answer:
41.67 mol
Explanation:
1 Litre of water = 1000g
Mole = mass / molar mass
Mass of 1 L of water = 1000 g
Molar mass of water (H2O) :
(H = 1, O = 16)
H2O = (1 * 2) + 16 = (2 + 16) = 18g/mol
Amount of water consumed = (3/4) of 1 litre
= (3/4) * 1000g
= 750g
Therefore mass of water consumed = 750g
Mole = 750g / 18g/mol
Mole of water consumed = 41.6666
= 41.67 mol
Answer:
The molar concentration of HCl in the aqueous solution is 0.0131 mol/dm3
Explanation:
To get the molar concentration of a solution we will use the formula:
<em>Molar concentration = mass of HCl/ molar mass of HCl</em>
<em></em>
Mass of HCl in the aqueous solution will be 40% of the total mass of the solution.
We can extract the mass of the solution from its density which is 1.2g/mL
We will further perform our analysis by considering only 1 ml of this aqueous solution.
The mass of the substance present in this solution is 1.2g.
<em>The mass of HCl Present is 40% of 1.2 = 0.48 g.</em>
The molar mass of HCl can be obtained from standard tables or by adding the masses of Hydrogen (1 g) and Chlorine (35.46 g) = 36.46g/mol
Therefore, the molar concentration of HCl in the aqueous solution is 0.48/36.46 = 0.0131 mol/dm3
Answer:
3224 kJ/mol
Explanation:
The combustion of benzoic acid occurs as follows:
C₇H₆O₂ + 13/2O₂ → 7CO₂ + 3H₂O + dE
The change in temperature in the reaction is the change due the energy released, that is:
3.256K * (10.134kJ / K) = 33.00kJ are released when 1.250g reacts
To find the heat released per mole we have to find the moles of benzoic acid:
<em>Moles benzoic acid -Molar mass: 122.12g/mol-:</em>
1.250g * (1mol / 122.12g) = 0.0102 moles
<em />
The dE combustion per mole of benzoic acid is:
33.00kJ / 0.0102moles =
<em>3224 kJ/mol </em>
