A physical change.
Physical change = can be reverted + doesn't change substance
Chemical = changes substance
Answer:
3p^2
Explanation:
after filling 3s^2 only two electrons left out of 14 so the next sub shell is 3p therefore ,X represents 3p^2
Answer:
Aqueous NaOH: <u>soluble
</u>
Aqueous NaHCO₃: <u>insoluble</u>
Aqueous Na₂CO₃: <u>soluble</u>
Explanation:
The organic acid is insoluble. Its salt (ionic) is soluble.
The important principle is:
If you have two acids in a flask, the stronger acid (smaller pKₐ) will protonate the weaker one. The stronger acid will become ionic and therefore more soluble.
1. In NaOH
Let's write the formula for 4-nitrobenzoic acid as HA.
The equation for the reaction is
HA + OH⁻ ⇌ A⁻ + H₂O
pKₐ: 7.15 15.7
HA is the stronger acid. It will protonate the hydroxide ion and be converted to the soluble 4-nitrobenzoate ion.
4-Nitrophenol is soluble in NaOH.
2. In NaHCO₃
HA + HCO₃⁻ ⇌ A⁻ + H₂CO₃
pKₐ: 7.15 6.36
HCO₃⁻ is the stronger acid. It will protonate 4-nitrophenol.
4-Nitrobenzoic acid is insoluble in NaHCO₃.
3. In Na₂CO₃
HA + CO₃²⁻ ⇌ A⁻ + H₂CO₃
pKₐ: 7.15 10.33
HA is the stronger acid. It will protonate the carbonate ion.
4-Nitrophenol is soluble in Na₂CO₃.
Answer :
<em><u>Explanation For The Three States OF Matter On the Basis OF Characteristics Of Particles / Molecules OF Matter.</u></em>
<h3><em><u>S</u></em><em><u>o</u></em><em><u>l</u></em><em><u>i</u></em><em><u>d</u></em><em><u>:</u></em><em><u> </u></em></h3>
<em><u>In solids the molecules are closely packed . There is a strong force of attraction between the molecules and the space between them is very small (almost negligible). The molecules are , therefore, not free to move . They merely vibrate their mean positions . This makes solids hard and difficult to compress , giving them a fixed shape and size.</u></em>
<h3><em><u>L</u></em><em><u>i</u></em><em><u>q</u></em><em><u>u</u></em><em><u>i</u></em><em><u>d</u></em><em><u> </u></em><em><u>:</u></em><em><u> </u></em></h3>
<em><u>In the case of liquids , the molecules are not closely packed. They do not attract each other as strongly as the molecules of solids. Thus, the intermolecular spaces are larger and the molecules are able to move about more freely . This makes liquid flow and take the shape of the container into which it is poured. Thus, liquids have a fixed volume but no def</u></em><em><u>i</u></em><em><u>nite shape of their own .</u></em>
<h3><em><u>G</u></em><em><u>a</u></em><em><u>s</u></em><em><u> </u></em><em><u>:</u></em><em><u> </u></em></h3>
<em><u>In the case of gases, the molecules hardly attract each other. They lie far a part from each other and the intermolecular spaces are, therefore, very large. . The intermolecular force of attraction is so weak that the molecules have great freedom of movement . As a result , gases have neither a fixed shapenor a fixed volume . They completely full up spacw available to them. They can be easily compressed as well, thus decreasing the gaps between their molecules .</u></em>
Explanation :
<h3><em><u>H</u></em><em><u>o</u></em><em><u>p</u></em><em><u>e</u></em><em><u> </u></em><em><u>i</u></em><em><u>t</u></em><em><u> </u></em><em><u>w</u></em><em><u>o</u></em><em><u>r</u></em><em><u>k</u></em><em><u>s</u></em><em><u> </u></em><em><u>o</u></em><em><u>u</u></em><em><u>t</u></em><em><u> </u></em><em><u>!</u></em></h3>