Enthalpy change is the term given to the concentration of the heat absorbed or evolved in a reaction carried out at a constant pressure. It is given by the symbol ΔH.
Enthalpy change = m (Cwater × dT + Hvap + Csteam × dT
dHvap = 40.67 kJ/mol = 40.67 × 103/18 = 2259.4 J/g
Enthalpy change = 5.00 [4.18 × (100-14) + 2259.4 + 1.84 × (115-100)]
= 13232.4 J
Answer:
Semiconductors are poor conductors at low temperatures, but their resistance decreases with increasing temperature.
Explanation:
A semiconductor can be defined as a crystalline solid substance that has its conductivity lying between that of a metal and an insulator, due to the effects of temperature or an addition of an impurity. Semiconductors are classified into two main categories;
1. Extrinsic semiconductor.
2. Intrinsic semiconductor.
The statement which best describes the electrical conductivity of metals and semiconductors is that semiconductors are poor conductors at low temperatures, but their resistance decreases with increasing temperature.
This ultimately implies that, semiconductors are typically an insulator (poor conductor) at low temperatures and a good conductor at high temperatures.
Additionally, conduction involves the transfer of electric charge or thermal energy due to the movement of particles. When the conduction relates to electric charge, it is known as electrical conduction while when it relates to thermal energy, it is known as heat conduction.
Answer:
Three double bonds and no lone pairs of electrons- trigonal planar
Two single bonds and two lone pairs of electrons-bent
Five single bonds and no lone pairs of electrons- trigonal bipyramidal
Three single bonds and one lone pair of electrons- trigonal pyramidal
Two double bonds and no lone pairs of electrons - linear
Four single bonds and no lone pairs of electrons- tetrahedral
Six single bonds and no lone pairs of electrons- octahedral
Explanation:
The valence shell electron pair repulsion theory gives a description of the shape of a molecule based on the number of regions of electron density present on the valence shell of the central atom of the molecule.
The molecules are distorted away from the shape predicted on the basis of the VSEPR by the presence of lone pairs on the valence shell of the central atom in the molecule. In the absence of lone pairs, the shape of a molecule is exactly the shape predicted on the basis of the VSEPR theory.
<u>Answer:</u> The 
for the reaction is -1406.8 kJ.
<u>Explanation:</u>
Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.
According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.
The chemical reaction for the formation reaction of 
is:
The intermediate balanced chemical reaction are:
(1) 
( × 6)
(2) 
( × 3)
(3) 
( × 2)
(4) 
The expression for enthalpy of formation of is,
![\Delta H^o_{formation}=[6\times \Delta H_1]+[3\times \Delta H_2]+[2\times \Delta H_3]+[1\times \Delta H_4]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Bformation%7D%3D%5B6%5Ctimes%20%5CDelta%20H_1%5D%2B%5B3%5Ctimes%20%5CDelta%20H_2%5D%2B%5B2%5Ctimes%20%5CDelta%20H_3%5D%2B%5B1%5Ctimes%20%5CDelta%20H_4%5D)
Putting values in above equation, we get:
![\Delta H^o_{formation}=[(-74.8\times 6)+(-185\times 3)+(323\times 2)+(-1049\times 1)]=-1406.8kJ](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Bformation%7D%3D%5B%28-74.8%5Ctimes%206%29%2B%28-185%5Ctimes%203%29%2B%28323%5Ctimes%202%29%2B%28-1049%5Ctimes%201%29%5D%3D-1406.8kJ)
Hence, the for the reaction is -1406.8 kJ.
near what like open flames? if so false unless it clarifies the solution requires alcohol then its a no go
