Answer:
pent-3-ene-1-yne
Explanation:
1 2 3 4 5
CH ≡ C - CH = CH - CH3
IUPAC name : Pent-3-ene-1-yne
Answer:
It takes 12,000 Joules of energy to melt 35 grams of ice at 0 °C
Explanation:
Good Luck!
Answer:
The correct answer is:
<em>(1) It is important that the sample is dissolved in just enough hot solvent. </em>
Explanation:
The process of recrystallization is important to eliminate the impurities and to obtain better crystals of the solid. The solvent used to perform the recrystallization must have a high dissolution power of the substance to be recrystallized and a low dissolution power of the impurities. This is in order to eliminate most impurities. Furthermore, <em>It is important that the sample is dissolved in just enough hot solvent </em>because this should be easy to remove after the recrystallization and the crystal should form easily when the solution cools. Also, it is better to add the hot solvent to solubilize the crystals and keep the impurities insoluble, instead of adding the cold solvent and heating the solution. Additionally, the process of cooling the solution must be done slowly to obtain large and fewer crystals. A fast ice-cooling will form smaller crystals.
Answer:
B. Particles of matter have spaces between them.
Explanation:
The particle nature model of matter is an model used to explain the properties and nature of matter. The statements of the particle nature model of matter are as follows :
1. Matter is made of small particles of atoms or molecules.
2. The particles of matter have space between them. The spaces between the particles are least in solids as they are closely packed together but are greatest in gases whose particles are far apart from each other.
3. The particles of matter are in constant motion at all times. Solids particles are not free to move due to strong molecular forces between the particles, but are constantly vibrating in their mean positions. Liquid particles free to move due to lesser molecular forces while gas molecules which have negligible intermolecular forces have the greatest ability to move.
4. The particles of matter are attracted to each other by intermolecular forces. These forces are greatest in solids and least in gases.
The correct option is B.
