Answer:
After the solution is heated, but before additional solute is added
Explanation:
An unsaturated solution is a solution that contains less solute than it can normally hold at a given temperature. Hence an unsaturated solution can still dissolve more solute.
When the solution is heated, the saturated cold solution becomes an unsaturated hot solution which is capable of dissolving more solute at this point.
Once more solute is dissolved, the solution becomes saturated again just before it begins to cool since no more solute dissolves in the solution at some point before cooling and addition of seed crystals.
Answer:
When you place the north pole of one magnet near the south pole of another magnet, they are attracted to one another.
Explanation:
Answer:
1. Nonmetals.
2. Likely to form anions (except the noble gases).
3. All of these
4. Easily reduced (except the noble gases).
Explanation:
Elements with high electronegativities are found towards the upper right corner of the Periodic Table. Thus, they have all the above properties.
Google said
How many electrons fit in each shell around an atom?
The maximum number of electrons that can occupy a specific energy level can be found using the following formula:
Electron Capacity = 2n2
The variable n represents the Principal Quantum Number, the number of the energy level in question.
Energy Level
(Principal Quantum Number) Shell Letter Electron Capacity
1 K 2
2 L 8
3 M 18
4 N 32
5 O 50
6 P 72
Keep in mind that an energy level need not be completely filled before electrons begin to fill the next level. You should always use the Periodic Table of Elements to check an element's electron configuration table if you need to know exactly how many electrons are in each level.
Answer:
b. ΔE rxn is a measure of heat
Explanation:
a. ΔHrxn is the heat of reaction. <em>TRUE. </em>ΔHrxn or change in enthalpy of reaction is per definition the change in heat that is involved in a chemical reaction.
b. ΔErxn is a measure of heat. <em>FALSE. </em>Is the change in internal energy of a reaction
c. An exothermic reaction gives heat off heat to the surroundings. <em>TRUE</em>. An exothermic reaction is a chemical reaction that releases heat.
d. Endothermic has a positive ΔH. <em>TRUE. </em>When a process is exothermic ΔH<0 and when the process is endothermic ΔH>0
e. Enthalpy is the sum of a system's internal energy and the product of pressure and volume. <em>TRUE. </em>Under constant pressure and volume the formula is ΔH = ΔE + PV
I hope it helps!