Answer: The standard enthalpy of formation of
is -252.1 kJ/mol.
Explanation:
The balanced chemical reaction is,
The expression for enthalpy change is,
Putting the values we get :
Thus standard enthalpy of formation of
is -252.1 kJ/mol.
Given:
Half life(t^ 1/2) :30 years
A0( initial mass of the substance): 200 mg.
Now we know that
A= A0/ [2 ^ (t/√t)]
Where A is the mass that remains after t years.
A0 is the initial mass
t is the time
t^1/2 is the half life
Substituting the given values in the above equation we get
A= [200/ 2^(t/30) ] mg
Thus the mass remaining after t years is [200/ 2^(t/30) ] mg
Answer:
The majority of the air we breathe is made up of nitrogen and oxygen, though you'll also find argon, carbon dioxide and other gases in trace amounts.
Explanation:
Answer:1:En química, el número másico o número de masa es la suma del número de protones y el número de neutrones del núcleo de un átomo. Se simboliza con la letra A (el uso de esta letra proviene de alemán Atomgewicht, que quiere decir peso atómico, aunque sean conceptos distintos que no deben confundirse).
2:
Answer:

Explanation:
Hello!
In this case, since the equation for the ideal gas is:

For each gas, given the total volume, temperature (28.1+273.15=301.25K) and moles, we can easily compute the partial pressure as shown below:

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