Answer:
The temperature at which rhenium becomes superconducting is -271.6 ºC.
Explanation:
We can convert the temperature given in Kelvin, which is an absolute scale, into degrees Celsius. which is a relative scale, by a simple algebraic translation, that is:
(1)
Where:
- Temperature, measured in degrees Celsius.
- Temperature, measured in Kelvins.
If we know that
, then the temperature given in degrees Celsius is:


The temperature at which rhenium becomes superconducting is -271.6 ºC.
Answer:
The final volume of the bubble is 7.13 mL.
Explanation:
The combined gas equation is,
where,
= initial pressure of gas = 3 atm
= final pressure of gas = 0.95 atm
= initial volume of gas =
= final volume of gas = ?
= initial temperature of gas =
= final temperature of gas =
Now put all the given values in the above equation, we get:

The final volume of the bubble is 7.13 mL.
Answer:
9.62moles of NH₃
Explanation:
Given parameters:
Number of moles of nitrogen = 4.81moles
Unknown:
Number of moles of NH₃ = ?
Solution:
To solve this problem, we need to establish a balanced reaction equation:
N₂ + 3H₂ → 2NH₃
Now, we can solve the problem by working from the known to the unknown.
1 mole of N₂ produced 2 moles of NH₃
4.81moles of N₂ will produce 2 x 4.81 = 9.62moles of NH₃
Answer: 31.55 g
Explanation:
- The mass number of Fluoride atom (F) = 18.99 g/mol, so mass number of fluorine gas (F2) = 37.98 g/mol.
- 1 mole of (F2) [which has 37.98 g/mol] contains Avogadro’s number of molecules (6.02×10^23 molecules),
so 1 mole of (F2) with 37.98 g/mol → 6.02×10^23 molecules.
- Using cross multiplication,
37.98 g/mol of (F2) → 6.02 ×10^23 molecules
? → 5.00 ×10^23 molecules
Hence the mass of 5.00×10^23 molecules of F2 = (37.98 × 5.00 × 10^23) / 6.02 ×10^23 = 31.55 g..
Answer:
ΔE negative,ΔE positive,ΔE positive
Explanation:
Internal energy change of a system is positive when the system acquires energy from outside and internal energy change is negative when energy is being liberated from the system.
a Sweat evaporates from skin,cooling the skin ΔE is negative as heat energy is liberated through evaporation of sweat.
b A balloon expand against an external pressure ΔE positive because external energy is required to expand the balloon.
c An aqueous chemical reaction mixture is warmed with an external flame ΔE is positive because heat energy is provided by the external flame to warm the aqueous chemical reaction.