Hello!
First you need to calculate q
<span>delta U is change in internal energy </span>
<span>delta U = q + w </span>
<span>q is heat and w work done </span>
<span>here work was done by the system means energy leaving the system so w is negative </span>
<span>delta U = q + w </span>
<span>q = delta U - w = 6865 J - (-346 J) = 7211 J = 7.211 KJ </span>
<span>q = m x c x delta T </span>
<span>7211 J = 80.0 g x c x (225-25) °C </span>
<span>c = 0.451 J /g °C
</span>
Hope this Helps! Have A Wonderful Day! :)
Answer:
1.2 liters.
Explanation:
Focus on the 4th digit: that's the ones column. The 3rd digit is the decimal place, just be sure to round up.
Answer:
atoms tend to react in order to gain 8 valence electrons
Explanation:
The octet rule describes the tendency of atoms of elements to react in order to have eight electrons in their valence shell. This is because having eight valence electrons confers stability to the atoms of these elements in the compounds they form.
The octet rule only does not apply to the transition elements or the inner transition elements as only the s and p electrons are involved. the electronic configuration in atoms having an octet is s²p⁶.
For example, sodium atom has one valence electron in its valence shell but a complete octet in the inner shell; it will react with chlorine atom which has seven valence electrons to form a stable compound, sodium chloride by donating its one valence electron in order to have an octet. Similarly, the chlorine atom will then have an octet by accepting the one electron from sodium atom.
The best answer for the question above would be the chloroflourocarbons or the CFCs. These chloroflourocarbons or CFCs are the ones responsible for the depletion of the ozone - which leads to leaving a hole in its layer. These gases eat out the ozone layer and allows harmful UV rays of the sun to come in the Earth.
Answer:
a) Unsaturated
b) Supersaturated
c) Unsaturated
Explanation:
A saturated solution contains the <u>maximum amount of a solute that will dissolve in a given solvent at a specific temperature</u>.
An unsaturated solution contains <u>less solute than it has the capacity to dissolve. </u>
A supersaturated solution, <u>contains more solute than is present in a saturated solution</u>. Supersaturated solutions are not very stable. In time, some of the solute will come out of a supersaturated solution as crystals.
According to these definitions and considering that the solubility of KCl in 100 mL of H₂O at <u>20 °C is 34 g</u>, and at <u>50 °C is 43 g</u> we can label the solutions:
a) 30 g in 100 mL of H₂O at 20 °C ⇒ unsaturated
b) 65 g in 100 mL of H₂O at 50 °C ⇒ supersaturated
c) 42 g in 100 mL of H₂O at 50 °C and slowly cooling to 20 °C to give a clear solution <u>with no precipitate</u> ⇒ unsaturated (if it were saturated it would have had precipitate)