Answer:
c and d are correct
Explanation:
In A, false because in Valence Electrons, the more the valences, the more stable an atom is.
In B, false because atoms cannot readily gain or lose valence electrons as the number of valence electrons is determined by the column they are in.
In C, true because the more the valence electrons, the more the stability of an atom.
In D, true as electron placing is important and the reactivity of an atom is important.
So C and D are true!
<span>Answer:
The HCl and KOH will react until one or the other is gone. As you have a larger volume of an equal concentration of HCl, the KOH will go first.
moles HCl = 0.04000 L * 0.100 M = 0.00400 moles
moles KOH = 0.02500 L * 0.100 M = 0.00250 moles
moles HCl left = 0.00400 - 0.00250 = 0.00150 moles
Your total volume is now 65.00 mL, so the [HCl] = 0.00150 moles / 0.06500 L = 0.0231 M = [H+]
pH = -log [H+] = -log (0.0231) = 1.64</span>
The balanced equation that illustrates the reaction is:
2C4H6 + 11O2 ......> 8CO2 + 6H2O
number of moles = mass / molar mass
number of moles of oxygen = 2.1 / 32 = 0.065625 moles
Now, from the balanced equation, we can note that:
11 moles of oxygen are required to produce 6 moles of water.
Therefore:
0.065625 moles of oxygen will produce:
(0.065625*6) / 11 = 0.03579 moles of water
number of moles = mass / molar mass
mass = number of moles * molar mass
mass of water = 0.03579 * 18 = 0.644 grams
<em>From the above options, the best </em><em>Thermal insulator </em><em>will be a </em><em>Plastic cup.</em>
Option (b);
<u>Explanation</u>
Thermal insulators resist to conduct energy or reduction of heat transfer when objects come across in contact with radiation or higher heat object. To conduct energy we need metal or those materials which contain free electrons in it to move from one metal to another.
Plastic doesn't have metallic character so it will resist the heat up to some threshold. Mostly this material is used in separating two current-conducting material. There are many other examples of thermal insulator such as Rubber, fabrics, paper, wood, wool.
Answer:
evaporation is most likely to occur on a warm sunny day
Explanation:
Evaporation rates are higher at higher temperatures because as temperature increases, the amount of energy necessary for evaporation decreases. In sunny, warm weather the loss of water by evaporation is greater than in cloudy and cool weather. ... So, sunny, hot, dry, windy conditions produce higher evaporation rates.
