Similarities between Mendeleev's periodic and Modern periodic table: Elements are arranged in groups and periods. Elements with similar properties are placed in the same group. Metals and non-metals are placed separately.
The major difference is that the elements in Mendeleev's periodic table were arranged by atomic mass and the modern periodic table arranges elements by atomic number. Of course as elements are constantly being discovered there were significantly fewer elements in Mendeleev's periodic table.
Explanation:
It is known that the change in Gibb's free energy varies with temperature as follows.
= ![\Delta H(T_{f}) - \Delta C_{p,m} (T - T_{f}) - T[\Delta S(T_{f}) - \Delta C_{p,m} ln (\frac{T}{T_{f}})]](https://tex.z-dn.net/?f=%5CDelta%20H%28T_%7Bf%7D%29%20-%20%5CDelta%20C_%7Bp%2Cm%7D%20%28T%20-%20T_%7Bf%7D%29%20-%20T%5B%5CDelta%20S%28T_%7Bf%7D%29%20-%20%5CDelta%20C_%7Bp%2Cm%7D%20ln%20%28%5Cfrac%7BT%7D%7BT_%7Bf%7D%7D%29%5D)
(assumption)
= 
= 
As, T = 
= (-3 + 273) = 270 K, 
.
Therefore, calculate the change in Gibb's free energy as follows.
= 
= -65.93 J/mol K + 0.62 J/mol K
= -65.31 J/mol K
Thus, we can conclude that Gibbs energy of freezing for the given reaction is -65.31 J/mol K.
Answer:
a. BH₃
Explanation:
According to the octet rules, atoms reach stability when are surrounded by eight electrons in their valence shell when they combine to form a chemical compound.
From the options, the only compound in which the central atom does not meet the octet rules is BH₃. The central atom is boron (B), which has 3 electrons in its valence shell. When B is combined with hydrogen (H), 3 electrons from the 3 atoms of H are added. <em>The total amount of electrons is 6</em>, <em>fewer than 8 electrons</em> needed to meet the rule.
I believe it's B: series circuit
good luck
Answer:
11.31 g.
Explanation:
Molarity is defined as the no. of moles of a solute per 1.0 L of the solution.
M = (no. of moles of solute)/(V of the solution (L)).
<em>∴ M = (mass/molar mass)of NaCl/(V of the solution (L)).</em>
<em></em>
<em>∴ mass of NaCl remained after evaporation of water = (M)(V of the solution (L))(molar mass)</em> = (0.45 M)(0.43 L)(58.44 g/mol) = <em>11.31 g.</em>
