Answer:
4.1 atm = 3,116 mmHg = 415.4 kPa
Explanation:
According to Boyle's law, as volume is increased the pressure of the gas is decreased. That can be expressed as:
P₁ x V₁= P₂ x V₂
Where P₁ and V₁ are the initial pressure and volume respectively, and P₂ and V₂ are final pressure and volume, respectively.
From the problem, we have:
V₁= 50.0 L
V₂= 68.0 L
P₂= 3.0 atm
Thus, we calculate the initial pressure as follows:
P₁= (P₂ x V₂)/V₁= (3.0 atm x 68.0 L)/(50.0 L)= 4.08 atm ≅ 4.1 atm
To transform to mmHg, we know that 1 atm= 760 mmHg:
4.1 atm x 760 mmHg/1 atm = 3,116 mmHg
To transform to kPa we use: 1 atm= 101.325 kPa
4.1 atm x 101.325 kPa = 415.4 kPa
Answer:

Explanation:
We are asked to find how many kilojoules of energy would be required to heat a block of aluminum.
We will use the following formula to calculate heat energy.

The mass (m) of the aluminum block is 225 grams and the specific heat (c) is 0.897 Joules per gram degree Celsius. The change in temperature (ΔT) is the difference between the final temperature and the initial temperature.
- ΔT = final temperature - inital temperature
The aluminum block was heated from 23.0 °C to 73.5 °C.
- ΔT= 73.5 °C - 23.0 °C = 50.5 °C
Now we know all three variables and can substitute them into the formula.
- m= 225 g
- c= 0.897 J/g° C
- ΔT= 50.5 °C

Multiply the first two numbers. The units of grams cancel.



Multiply again. This time, the units of degrees Celsius cancel.


The answer asks for the energy in kilojoules, so we must convert our answer. Remember that 1 kilojoule contains 1000 joules.

Multiply by the answer we found in Joules.




The original values of mass, temperature, and specific heat all have 3 significant figures, so our answer must have the same. For the number we found, that is the tneths place. The 9 in the hundredth place tells us to round the 1 up to a 2.

Approximately <u>10.2 kilojoules</u> of energy would be required.
Answer:
increase
Explanation:
Conduction involves the transfer of electric charge or thermal energy due to the movement of particles. When the conduction relates to electric charge, it is known as electrical conduction while when it relates to thermal energy, it is known as heat conduction. Conductors include metal, steel, aluminum, copper, frying pan, pot, spoon etc.
In the process of heat conduction, thermal energy is usually transferred from fast moving particles to slow moving particles during the collision of these particles. Also, thermal energy is typically transferred between objects that has different degrees of temperature and materials (particles) that are directly in contact with each other but differ in their ability to accept or give up electrons.
Hence, thermal energy added to a substance that is not changing state causes the substance’s temperature to increase because it would absorb energy in the form of heat.
When oxygen is found is peroxide, it has an oxidation number of -1.
The chemical formula of hydrogen peroxide is H2O2. We know that hydrogen always has +1 oxidation state until it forms metal hydrides. So in H2O2, the oxidation state ofhydrogen is +1.
Now, let oxidation state of oxygen be x. So,
2 * (+1) + 2*x = 0
2 + 2x = 0
2x = -2
x = -2 / 2
x = -1
Hence, the oxidation number of oxygen in peroxides is -1