Answer:
True.
Explanation:
An exothermic reaction has a positive enthalpy (heat) of reaction. However, it can be negative in some circumstances.
Answer:
The final temperature of hydrogen gas is 537.63 K.
Explanation:
Given data:
Initial volume = 2.00 L
Initial pressure = 740 mmHg (740/760 = 0.97 atm)
Initial temperature = 25 °C (25 +273 = 298 K)
Final temperature =?
Final volume = 3.50 L
Final pressure = standard = 1 atm
Formula:
According to general gas equation:
P₁V₁/T₁ = P₂V₂/T₂
P₁ = Initial pressure
V₁ = Initial volume
T₁ = Initial temperature
P₂ = Final pressure
V₂ = Final volume
T₂ = Final temperature
Solution:
P₁V₁/T₁ = P₂V₂/T₂
T₂ = P₂V₂T₁ / P₁V₁
T₂ = 1 atm × 3.5 L × 298 K / 0.97 atm × 2.00 L
T₂ = 1043 atm .L. K / 1.94 atm. L
T₂ = 537.63 K
Answer:
Amount of excess Carbon (ii) oxide left over = 23.75 g
Explanation:
Equation of the reaction: Fe₂O₃ + 3CO ----> 2Fe + 3CO₂
Molar mass of Fe₂O₃ = 160 g/mol;
Molar mass of Carbon (ii) oxide = 28 g/mol
From the equation of reaction, 1 mole of Fe₂O₃ reacts with 3 moles of carbon (ii) oxide; i.e. 160 g of iron (iii) oxide reacts with 84 g (3 * 28 g) of carbon (ii) oxide
450 g of Fe₂O₃ will react with 450 * 84/180) g of carbon (ii) oxide = 236..25 g of carbon (ii) oxide
Therefore the excess reactant is carbon (ii) oxide.
Amount of excess Carbon (ii) oxide left over = 260 - 236.25
Amount of excess Carbon (ii) oxide left over = 23.75 g
Mass = m = 40 grams
Volume = V = 9 cm³
Density = d = ?
Density is defined as the ratio of mass and volume.
So,
d = m/V
Using the values, we get
d = 40/9 = 4.44 g/cm³
This means the density of material would be 4.44 g/cm³