This is from dictionary: <span>a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
I would say it is 2</span>
Okay
Mr (H2O)= 18g
therefore moles of H2O
is 720.8/18= 40.04mol
the ratio of H2 to O2 to H2O is
2 : 1 : 2
so moles of H2 is same as H2O here
H2= 40.04moles
moles of O2 is half
so 40.04 x 0.5
20.02moles
grams of O2 is
its moles into Mr of O2
that's 20.02 x 32 = 640.64g
Answer:Temperature increases
Explanation: As the gas in the container is an ideal gas so it should follow the ideal gas equation, the equation of state.
We know ideal gas equation to be PV=nRT where
P=pressure
V=Volume
T=Temperature
R=Real gas constant
n=Number of moles
since the gas is insulated such that no heat goes into or out of the system .
When we compress the ideal gas using a piston, Thermodynamically it means that work is done on the system by the surroundings.
Now as the ideal gas is been compressed so the volume of the gas would decrease and slowly a time will reach when no more gas can be compressed that is there cannot be any further decrease in volume of the gas.
From the equation PV=nRT
Once there is no further compression is possible hence volume becomes constant so pressure of the ideal gas becomes directly proportional to the temperature as n and R are constants. Also as the pressure and volume are inversely related so an decrease in volume would lead to an increase in pressure.
As the ideal gas is compressed so the pressure of the gas would increase since the gas molecules have smaller volume available after compression hence the gas molecules would quite frequently have collisions with other gas molecules or piston and this collision would lead to increase in speed of the gas molecules and so the pressure would increase .
The increase in pressure would lead to an increase in temperature as show by the above ideal gas equation because the pressure and temperature are directly related.
So here we can say that work done on the system by surroundings leads to increase in temperature of the system.
The constant used for the absorption of heat by the sample in melting is 
. Thus, option A is correct.
The chemical reaction has been defined as the energy in which the energy has been released or absorbed for the breaking of bonds in the reactants and the formation of product.
<h3>Constant for energy absorbed</h3>
The energy has been absorbed in the melting of the copper sample. Thus, the sample has been converted from the solid to the liquid state.
The change in energy with the conversion in solid and liquid state has been termed as heat of fusion.
The energy has been absorbed by the system, thus it has been marked with the positive sign.
Therefore, has been the constant used for the absorption of heat by the sample in melting. Thus, option A is correct.
Learn more about melting sample, here:
brainly.com/question/8828503
The correct answer that explains similarities between metal and Metalloids as regards the question is They both conduct electricity
- Metalloids can be regarded as elements that are similar to metals, this is because they posses valence orbitals which is described as highly delocalized over macroscopic volumes.
- As a result of this they can serve as electrical conductors.
- metalloids posses small energy gap which is located between the valence band as well as the conduction band, as a result of this they are considered as intrinsic semiconductors when compare to pure conductors like metal.
- Example of metal is Calcium, sodium and that of Metalloids are silicon and germanium
Therefore, metal and Metalloids are similar because of their conductivity of electricity
Learn more at: brainly.com/question/21036799?referrer=searchResults
