Answer:
728.9 torr
Explanation:
Collecting a gas over water results in gathering a mixture of gases. First of all, the target gas is collected, but the gathered sample also contains saturated water vapor.
The saturated water vapor always produces the same pressure which depends on temperature. At a given temperature of 23 degrees Celsius, the saturated vapor pressure is equal to 21.1 torr.
The total pressure is equal to the sum of partial pressures of water and hydrogen:
Solving for the partial pressure of hydrogen:
Answer : The enthalpy for the reaction is 49.1 kJ/mol
Explanation :
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The formation reaction of 
will be,
The intermediate balanced chemical reaction will be,
(1) 
(2) 
(3) 
Now we will reverse the reaction 1 and divide by 2, multiply reaction 2 by 6 and reaction 3 by 3/2 then adding all the equations, we get :
(1) 
(2) 
(3) 
The expression for enthalpy of formation of will be,
Therefore, the enthalpy for the reaction is 49.1 kJ/mol
Answer:
D: to transport materials through the body.
Explanation:
A: to bring oxygen into the lung. is incorrect because it's respiratory system
B: to put carbon dioxide into all the blood vessels carbon dioxide is exhaled out of the body
C: to expel waste products from the body. is excretory system
Answer:
The electrons that whiz about outside the nucleus have a negative charge. They are held in the atom by the positive charge of the nucleus. ... An atom that gains or loses an electron becomes an ion. If it gains a negative electron, it becomes a negative ion.
Explanation:
Hope this helped!...
