We write DE = q+w, where DE is the internal energy change and q and w are heat and work, respectively.
(b)Under what conditions will the quantities q and w be negative numbers?
q is negative when heat flows from the system to the surroundings, and w is negative when the system does work on the surroundings.
As an aside: In applying the first law, do we need to measure the internal energy of a system? Explain.
The absolute internal energy of a system cannot be measured, at least in any practical sense. The internal energy encompasses the kinetic energy of all moving particles in the system, including subatomic particles, as well as the electrostatic potential energies between all these particles. We can measure the change in internal energy (DE) as the result of a chemical or physical change, but we cannot determine the absolute internal energy of either the initial or the final state. The first law allows us to calculate the change in internal energy during a transformation by calculating the heat and work exchanged between the system and its surroundings.
Answer: B its most likely
Answer : The mass of oxygen per gram of sulfur for sulfur dioxide and sulfur trioxide is, 0.997 g and 1.5 g respectively.
Explanation : Given,
Mass of oxygen in sulfur dioxide = 3.49 g
Mass of sulfur in sulfur dioxide = 3.50 g
Mass of oxygen in sulfur trioxide = 9.00 g
Mass of sulfur in sulfur trioxide = 6.00 g
Now we have to calculate the mass of oxygen per gram of sulfur for sulfur dioxide and sulfur trioxide.
Mass of oxygen per gram of sulfur for sulfur dioxide =
Mass of oxygen per gram of sulfur for sulfur dioxide =
and,
Mass of oxygen per gram of sulfur for sulfur trioxide =
Mass of oxygen per gram of sulfur for sulfur trioxide =
Thus, the mass of oxygen per gram of sulfur for sulfur dioxide and sulfur trioxide is, 0.997 g and 1.5 g respectively.
Answer:
Physical change
Explanation:
Physical change -
It is the type of reversible change , where there is change in the state of the matter , is referred to as a physical change .
There is no chemical process involved during state change , i.e. , no new substance is formed .
Hence , from the given statement of the question, the correct term is physical change.
Answer:
92.37°C
Explanation:
Assuming the volume remains the same in both the states ( bicycle tire).
Then as per ideal gas equation
where P1, P2 are pressure at two different states and T1, T2 are temperature at these two states
Given:
P1 = 1.34 atm, T1 = 33.0 ° C = 306K
P2 = 1.60 atm, T2 = ?
1.34/306 = 1.60/T_2
⇒ T2 = 1.60×306/1.34
= T2= 365.37K= 92.37°C