Answer:
What percent of physically assaulted or abused adolescents reported lifetime substance abuse or dependence? Select one:
d. 25 percent
Explanation:
The study performed at the National Institute of Justice in 2003, called "Youth Victimization: Prevalence and Implications", Washington, D.C., U.S. Department of Justice, showed a rate of lifetime substance abuse or dependence at approximately 25 percent for adolescents who had been physically assaulted or abused. This compares to a rate of approximately six percent for adolescents who had not been physically assaulted or abused.
Explanation:
As per the 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.
Hence, 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. This means that the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
..........(1)
..............(2)
The final reaction is as follows:
.............(3)
Therefore, adding (1) and (2) we get the final equation (3) and value of
at 298 K will be as follows.
=
+
= -314 kJ + (-80) kJ
= -394 kJ
Thus, we can conclude that
at 298 K for the given process is -394 kJ.
Oxidation number of fe in the compound...,
Let the oxidation number of (Fe) be x
The oxidation number of oxygen(o) is (-2)
; 3x + 4(-2) = 0...where zero is the total charge on the compound(fe3o4)
; 3x = 8...then divide both sides by 3
Oxidation number of fe is( 2.67 )