Answer: A) Inconclusive; you would not know which of the two variables caused the change.
Explanation:
When you set up an experiment, you must make sure that you control the variables such that only one independent variable changes at a time, while all the remainder conditions (the other independent variables) are controlled (fixed).
By observing (measuring) the dependent variable, while only one independent variable changes you can understandhow such independent variable explains (determines) the dependent variable, leading to a conclusion.
Conversely, if two or more independent variables change at a time, then there is no way that you can tell how the output (dependent variable) is related with one or other of the changes of the indipendent variables. You wolud not be able to discriminate (distinguish) the effect of one or other variable, making the experiment inconclusive
I really hope this answer helps you out! It makes my day helping people like you and giving back to the community that has helped me through school! If you could do me a favor, if this helped you and this is the very best answer and you understand that all of my answers are legit and top notch. Please mark as brainliest! Thanks and have a awesome day!
Enthalpy is a state function
Explanation:
The Hess's law allows us to determine the enthalpy change of a reaction because enthalpy is a state function. It does not depend on the individual path take in going from reactants to products in the reaction.
- Enthalpy changes are the heat changes accompanying physical and chemical changes.
- It is the difference between the heat content of product in the final state and the reactants.
- Enthalpy changes for some reactions are not easily measurable experimentally.
- To calculate such heat changes, we apply the Hess's law of heat summation.
- The law states that "the heat change of a reaction is the same whether it occurs in a step or several steps".
- The Hess's law is simply based on the first law of thermodynamics by which we know that energy is conserved in every system.
learn more:
Hess's law brainly.com/question/11293201
#learnwithBrainly
I think the half of 1293 its the mass ? maybe idk I just tried
Answer is d. in hetrogeneous you can separate things from each other
Answer:
pKa = 3.675
Explanation:
∴ <em>C</em> X-281 = 0.079 M
∴ pH = 2.40
let X-281 a weak acid ( HA ):
∴ HA ↔ H+ + A-
⇒ Ka = [H+] * [A-] / [HA]
mass balance:
⇒<em> C</em> HA = 0.079 M = [HA] + [A-]
⇒ [HA] = 0.079 - [A-]
charge balance:
⇒ [H+] = [A-] + [OH-]... [OH-] is negligible; it comes from to water
⇒ [H+] = [A-]
∴ pH = - log [H+] = 2.40
⇒ [H+] = 3.981 E-3 M
replacing in Ka:
⇒ Ka = [H+]² / ( 0.079 - [H+] )
⇒ Ka = ( 3.981 E-3 )² / ( 0.079 - 3.981 E-3 )
⇒ Ka = 2.113 E-4
⇒ pKa = - Log ( 2.113 E-4 )
⇒ pKa = 3.675
