In general terms, exothermic reactions release energy, so the energy goes from the system to the surroundings.
Answer:
See explanation
Explanation:
When a beaker of ethanoic acid is placed in the refrigerator, its temperature drops and the vessel feels cool.
Now, when we mix ethanoic acid and sodium carbonate, an endothermic reaction occurs, fizzing is observed as carbon dioxide is given off and heat is lost to the surroundings causing the reaction vessel to feel cool to touch.
The difference between putting ethanoic acid in the refrigerator and adding sodium carbonate to the solution is that, in the former, no new substance is formed. The substance remains ethanoic acid when retrieved from the refrigerator. In the later case, new substances are formed. The substance is no more ethanoic acid because a chemical reaction has taken place.
Answer:
1.84 L
Explanation:
Using the equation for reversible work:

Where:
W is the work done (J) = -287 J.
Since the gas did work, therefore W is negative.
P is the pressure in atm = 1.90 atm.
However, work done is in joules and pressure is in atm. We can use the values of universal gas constant as a convenient conversion unit. R = 8.314 J/(mol*K); R = 0.0821 (L*atm)/(mol*K)
Therefore, the conversion unit is 0.0821/8.314 = 0.00987 (L*atm)/J
is the initial volume = 0.350 L
is the final volume = ?
Thus:
(-287 J)*0.00987 (L*atm)/J = -1.9 atm*(
- 0.350) L
= [(287*0.00987)+(1.9*0.350)]/1.9 = (2.833+0.665)/1.9 =1.84 L
Answer:
c
Explanation:
the correct answer would be answer c
Acid-base indicator changes color based on pH.
drop some in a solution n watch the color changes. different indicators show different colors at different pH. they usually have standard colors for comparison.