Answer:
- <em>A compound that conducts an electric current in aqueous solution or in the molten state is</em> a <u>ionic compound</u>.
Explanation:
Some examples of ionic compounds are NaCl, KF, KI, MgSO₄.
Ionic compounds are formed by positivie ions (named cations) and negative ions (named anions). The strong electrostatic atraction between cations and anions permits the formation of crystals, which are stuctures characterized by a regular pattern. In solid state the ions are in fixed positions.
In order to conduct electricity, the charged particles (cations and anions in the case of the ionic compounds) need to move freely.
Hence, since in solid state, ionic compounds do not conduct electric current. But, <em>in molten (liquid) state or in aqueous solution, ionic compounds conduct electric current because, then, the ions move freely.</em>
Answer:
<u>Potential energy is</u> the stored energy in an object or thing, while <u>kinetic energy is</u> the energy which an object contains because of a particular motion.
Explanation:
Answer: Li is the reducing agentg and O is the oxidizing agent.
Explanation:
1) The oxidizing agent is the one that is reduced and the reducing agent is the one that is oxidized.
2) The given reaction is:
4Li(s) + O₂ (g) → 2 Li₂O(s)
3) Determine the oxidation states of each atom:
Li(s): oxidation state = 0 (since it is alone)
O₂ (g): oxidation state = 0 (since it is alone)
Li in Li₂O (s) +1
O in Li₂O -2
That because 2× (+1) - 2 = 0.
4) Determine the changes:
Li went from 0 to + 1, therefore it got oxidized and it is the reducing agent.
O went from 0 to - 2, therefore it got reduced and it is the oxidizing agent.
Answer:
117.3 W is being removed.
Explanation:
The heat removed can be calculated as:
Q = m*c*ΔT
Where m is the mass, c is the specific heat and ΔT is the temperature variation. Because there're two components:
Q = mwater*cwater*ΔT + maluminum*caluminum*ΔT
Q = (mwater*cwater + maluminum*caluminum)*ΔT
Searching in a thermodynamic table:
cwater = 4.184 J/g°C
caluminium = 0.9 J/g°C
In 1 minute, the temperature decreases 2.2°C, so ΔT = -2.2°C
Q = (700*4.184 + 300*0.9) * (-2.2)
Q = -7037.36 J
The rate of energy is the potency (P), which is the heat divided by the time. So, for 1 minute (60 s):
P = -7037.36/60
P = -117.3 J/s
P = -117.3 W
The minus signal indicates that the energy is being removed.
