The sample of oxygen gas was collected through water displacement. So, the gas collected will be a mixture of oxygen and water vapor.
Given that the total pressure of the mixture of gases containing oxygen and water vapor = 749 Torr
Vapor pressure of pure water at 
=25.81mmHg
= 
According to Dalton's law of partial pressures,
Total pressure = Partial pressure of Oxygen gas + Partial pressure of water
749 Torr = Partial pressure of Oxygen gas + 25.81 Torr
Partial pressure of Oxygen gas = 749 Torr - 25.81 Torr = 723.19 Torr
Therefore the partial pressure of Oxygen gas in the mixture collected will be 723.19 Torr
Answer:- 2,1
Explanations:- Water is 
and from it's formula it is clear that the ratio of H to O moles or atoms is 2:1 means two hydrogen atoms for each oxygen atom. No matter what amount of water we have, the ratio of H atoms to O atoms is always same.
Hence, the answer is 2,1.
Q, R, S, P is the order of apparent magnitude of the stars, starting from the least to the greatest.
Answer: Q, R, S, P
<u>Explanation:</u>
The apparent magnitudes of the star is the brightness calculated by an observer at a particular distance from the Earth. The smaller the distance between the star and the Earth, the greater the apparent brightness.
So , from the given distance (in light years), Q,R,S,P is the answer (least to the greatest apparent magnitude) (distance is greatest to least).
In society today, I’d say T
Let's apply the principle of conservation of energy.
Heat of metal = Heat of water
mCmetalΔT = mCwaterΔT
Applying the given values,
(45 g)(Cmetal)(100 - 28 °C) = (130 g)(4.18 J/g-°C)(28 - 25 °C)
Solving for Cmetal,
<em>Cmetal = 0.503 J/g°C
Therefore, the heat capacity of the unknown metal is 0.503 J/g</em>°C.
