Answer:
1. Volume as STP = 755 L
2. Outside temperature = 255 K
3. Percentage yield = 70.5%
Explanation:
1. At STP, pressure = 101.3 kpa, temperature = 0°C or 273.15 K
Using the general gas equation :
P1V1/T1 = P2V2/T2
P1 = 620 kpa
V1 = 140 L
T1 = 37°C or (273.15 + 37) K = 310.15 K
P2 = 101.3 kpa
V2 = ?
T2 = 273.15 K
V2 = P1V1T2/P2T1
V2 = 620 × 140 × 273.15 / 101.3 × 310.15
V2 = 755 L
2. Using Charles' gas law:
V1/T1 = V2/T2
V1 = 2.5 L
T1 = 290 K
V2 = 2.2 L
T2 = ?
T2 = V2T1/VI
T2 = 2.2 × 290 / 2.5
T2 = 255 K
3. Equation of reaction : 2 Al + 3 CuSO4 ---> Al2 (SO4)3 + 3 Cu
From equation of the reaction, 2 moles of Al produces 3 moles of Cu
Molar mass of Al = 27 g; Molar mass of Cu = 63.5 g
2 moles of Al = 2 × 27 g = 54 g; 3 moles of Cu = 3× 63.5 = 190.5 g
54 g of Al produces 190.5 g of Cu
1.87 g of Al will produce 190.5/54 × 1.87 g of Cu = 6.60 g of Cu
Percentage yield = actual yield /theoretical yield × 100%
Percentage yield = 4.65/6.60 × 100%
Percentage yield = 70.5%
31 protons 31 electrons and 39 nutrons
The energy release when dissolving 1 mol of NaOH in water is 445.1 kJ
the mass of NaOH to be dissolved is 32.0 g
The number of NaOH moles in 32.0 g - 32.0 g / 40 g/mol = 0.8 mol
the energy released whilst dissolving 1 mol of NaOH - 445.1 kJ
when dissolving 0.8 mol - the energy released is 445.1 kJ/mol x 0.8 mol
therefore heat released is - 356.08 kJ
answer is -356.08 kJ
Intermolecular forces of attraction hold the molecules together. These forces determine the physical properties of substances like melting and boiling points. There are five types of intermolecular forces: Hydrogen bonding, dipole-dipole interactions, ionic interactions, ion-dipole interactions and dispersion forces.
Hydrogen bonding is a stronger force of attraction between hydrogen atom and an electronegative atom (F, N, and O). So, water molecules exhibit hydrogen bonding.
In carbon dioxide molecules, although each C=O is polar the molecule as a whole will be non polar due to symmetry. Therefore, the only intermolecular forces in CO2 will be dispersion forces.
Hence, Hydrogen bonding exists between water molecules but not carbon dioxide molecules.
Answer:
The acid will be neutralized overtime
Explanation:
The presence of the pyrites leads to the leaching of large amounts of sulphuric acid, however the basic carbonates neutralizes the acid according to the reaction equation;
CaCO3 + H2SO4 ---> CaSO4 + CO2 + H2O.
This will prevent all the deleterious consequences associated with the leaching of the acid in the abandoned coal mine.
