Answer:
The change in enthalpy is +210 kJ, so it is an endothermic reaction.
Explanation:
- The change in enthalpy shows that the reaction is exothermic or endothermic.
The change in enthalpy = The energy of products - the energy of reactants.
- If ΔH is positive value, the reaction is endothermic, the energy of the products is higher than that of the reactants.
- If ΔH is negative value, the reaction is exothermic, the energy of the products is lower than that of the reactants.
<em>For this reaction: </em>The change in enthalpy = The energy of products - the energy of reactants = 370 kJ - 160 kJ = + 210 kJ.
<em>So, the right choice is: The change in enthalpy is +210 kJ, so it is an endothermic reaction.</em>
Question:
What's the article about?
The formula for solving current given with resistance and power source or voltage is shown below:
I = V/R
When two 5 ohms resistors are in series, we have:
I = 9 volts / (5+5 ohms)
I = 0.9 amperes
When it is being added with another 7.5 resistors, we have:
I = 9 volts / (5+5+7.5 ohms)
I = 0.529 ampere
The answer to the question is the letter "D. decrease; 0.51 amps".
Answer:
b) +2 and +3.
Explanation:
Hello,
In this case, given the molecular formulas:

And:

We can relate the subscripts with the oxidation states by knowing that they are crossed when the compound is formed, for that reason, we notice that oxygen oxidation state should be -2 for both cases and the oxidation state of X in the first formula must be +2 since both X and O has one as their subscript as they were simplified:

Moreover, for the second case the oxidation state of X should be +3 in order to obtain 3 as the subscript of oxygen:

Thus, answer is b)+2 and +3
Best regards.
I'm not exactly sure which one but I do know that an acid and a base react in a aqueous solution to form water, so i would probably eliminate the ones that aren't aqueous solutions.