The amount of heat given by the water to the block of ice can be calculated by using
![Q=m_w C_{sw} \Delta T_w](https://tex.z-dn.net/?f=Q%3Dm_w%20C_%7Bsw%7D%20%5CDelta%20T_w)
where
![m_w = 30 g](https://tex.z-dn.net/?f=m_w%20%3D%2030%20g)
is the mass of the water
![C_{sw}=4.18 J/(g ^{\circ}C)](https://tex.z-dn.net/?f=C_%7Bsw%7D%3D4.18%20J%2F%28g%20%5E%7B%5Ccirc%7DC%29)
is the specific heat capacity of water
![\Delta T_w = 45.0^{\circ}-19.5^{\circ}C = 20.5^{\circ}C](https://tex.z-dn.net/?f=%5CDelta%20T_w%20%3D%2045.0%5E%7B%5Ccirc%7D-19.5%5E%7B%5Ccirc%7DC%20%3D%2020.5%5E%7B%5Ccirc%7DC)
is the variation of temperature of the water.
Using these numbers, we find
![Q=(30 g)(4.18 J/(g^{\circ}C))(20.5^{\circ}C)=2571 J](https://tex.z-dn.net/?f=Q%3D%2830%20g%29%284.18%20J%2F%28g%5E%7B%5Ccirc%7DC%29%29%2820.5%5E%7B%5Ccirc%7DC%29%3D2571%20J)
This is the amount of heat released by the water, but this is exactly equal to the amount of heat absorbed by the ice, used to melt it into water according to the formula:
![Q = m_i L_f](https://tex.z-dn.net/?f=Q%20%3D%20m_i%20L_f)
where
![m_i](https://tex.z-dn.net/?f=m_i)
is the mass of the ice while
![L_f =334 J/g](https://tex.z-dn.net/?f=L_f%20%3D334%20J%2Fg)
is the specific latent heat of fusion of the ice.
Re-arranging this formula and using the heat Q that we found previously, we can calculate the mass of the ice:
Answer:
Explanation:
Check the attachment for solution
Answer:
Alternating current
Explanation:
The electrical current periodically changes direction.
Answer:
2412 psi is the pressure of the gas mixture in the tank.
Explanation:
Pressure of the helium gas = 1,906 psi
Volume of the helium gas = 7.25 L
Pressure of the oxygen gas = 506 psi
Volume of the oxygen gas = 7.25 L
After mixing both gases in a container with volume 7.25 L at with constant temperature.
Since, the temperature and volume remained constant, pressure becomes directly dependent on moles of gases.So, when we mix gases together the moles of gases will also add and along with that pressure of individual gas will also get added to give total pressure of the mixture in a tank.
Total pressure = pressure(Heluim)+pressure(oxygen)
![P_{total}=1,906 psi+506 psi=2,412 psi](https://tex.z-dn.net/?f=P_%7Btotal%7D%3D1%2C906%20psi%2B506%20psi%3D2%2C412%20psi)
2412 psi is the pressure of the gas mixture in the tank.