Answer:
-179.06 kJ
Explanation:
Let's consider the following balanced reaction.
HCl(g) + NaOH(s) ⟶ NaCl(s) + H₂O(l)
We can calculate the standard enthalpy change for the reaction (ΔH°r) using the following expression.
ΔH°r = 1 mol × ΔH°f(NaCl(s)) + 1 mol × ΔH°f(H₂O(l)) - 1 mol × ΔH°f(HCl(g)) - 1 mol × ΔH°f(NaOH(s))
ΔH°r = 1 mol × (-411.15 kJ/mol) + 1 mol × (-285.83 kJ/mol) - 1 mol × (-92.31 kJ/mol) - 1 mol × (-425.61 kJ/mol)
ΔH°r = -179.06 kJ
Answer is. gas <span>has the highest entropy.
</span>Entropy is the measure of the molecular disorder<span> and it is system’s thermal </span>energy<span> per unit </span>temperature<span> that is unavailable for doing useful </span>work<span>.
Nitrogen molecules have weakest intermolecular bonds in gas phase and move fast and without order. In solid state movement is much more less.
</span><span>
</span>
<u>Given:</u>
Calculated density values-
Aluminum = 2.7 g/cm3
Copper = 9.0 g/cm3
Iron = 7.9 g/cm3
Titanium = 4.8 g/cm3
Unknown sample mass = 9.5 g
Sample volume = 2.1 cm3
<u>To determine:</u>
The identity of the unknown sample
<u>Explanation:</u>
'Density' is a physical parameter which can be used to identify the nature of the unknown substance.
Density = Mass/Volume
For the unknown sample
Density = 9.5 g/2.1 cm3 = 4.52 g/cm3
This matches closely with the calculated density of titanium
Ans: The unknown substance is made of titanium
Answer:
1) HCOOCH3
2) CH3CH2COOCH3
3) CH3CH2CH2CH(CH3)COOCH3
Explanation:
In the reaction between an alcohol and a carboxylic acid, an ester and water are formed. It is analogous to the inorganic neutralization reaction but this reaction is called esterification in organic chemistry. Esters contain the general formula RCOOR where the RCOO moiety was obtained from the acid and the other R moiety was obtained from the alcohol. The -COOR shows the ester linkage in the molecule. The condensed structural formulas shown in the answer reflects these facts.
First, find out how many grams are in one mole of CO2(the two oxygen atoms means you need to multiply oxygen’s amu by 2,then add whatever carbon’s amu is to that). Then divide 26 grams by that number and that will be your moles. There are only two significant figures, so round your answer correctly.
