Answer:
The final state of the substance is a gas.
The sample is initially a liquid. One or more phase changes will occur.
Explanation:
Let's consider the phase diagram for Argon (not to scale).
<em>A sample of argon is initially at a pressure of 49.6 atm and a temperature of 101.4 K. The pressure on the sample is reduced to 0.680 atm at a constant temperature of 101.4 K. Which of the following are true? Choose all that apply </em>
<em>The final state of the substance is a gas.</em> TRUE. At 0.680 atm and 101.4 K, the substance is a gas.
<em>The gas initially present will solidify.</em> FALSE. Initially, Ar is present as a liquid.
<em>The final state of the substance is a solid.</em> FALSE.
<em>The sample is initially a liquid. One or more phase changes will occur.</em> TRUE. The sample is initially liquid and only one phase change will occur.
Answer:
28.75211 kj
Explanation:
Given data:
Mass of iron bar = 841 g
Initial temperature = 84°C
Final temperature = 7°C
Heat released = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
specific heat capacity of iron is 0.444 j/g.°C
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 7°C - 84°C
ΔT = -77°C
By putting values,
Q = 841 g × 0.444 j/g.°C × -77°C
Q = 28752.11 j
In Kj:
28752.11 j × 1 kJ / 1000 J
28.75211 kj
The higher the current, the more likely it is lethal. Since current is proportional to voltage when resistance is fixed (ohm's law), high voltage is an indirect risk for producing higher currents.
Answer:
The correct answer is option D which is the decreasing order of conductivity is Mn, O, Ge.
Explanation:
You can easily answer this if you know the periodic trends. For the property of electrical conductivity, it decreases across a period and decreases also down a group. Thus, the most conductive element must be Mn, while the least conductive one is Ge. So, the answer is: -Mn, O, Ge
The number of oxygen atoms are 6 atoms
<u><em>Explanation</em></u>
According to the law of mass conservation the number of reactant atoms is equal to number of product atoms.
For given equation to obey the law of mass conservation it need to be balanced as below
4 Al + 3 O₂ → 2 Al₂O₃
Al₂O₃ is the product,therefore the number of oxygen atom
= coefficient in front of Al₂O₃ × subscript of O
=2 x 3 = 6 atoms
