Answer:
The diameter of Neptune is approximately 49,500 km. This makes Neptune the 4th largest planet in the Solar System, after Jupiter, Saturn and Uranus.
Answer:
Strong Surface Tension, Covalent Bonds, Denser as a Liquid, Polar.
Explanation:
Water is a polar substance with strong surface tension. It is denser as a liquid than as a solid. A water molecule consists of a hydrogen atom covalently bonded to two oxygen atoms.
Answer:
Concentration of the solution is 0.376M
Explanation:
Lambert-Beer's law describes the absorbance of a solution that is directely proportional to concentration of the solution, molar absorptivity and path length. The law is:
A = ε×C×l
<em>Where A is absorbance (0.699 for Red Dye #3), ε is molar absorptivity (1.217L mol⁻¹cm⁻¹), C is concentration of solution and l is path length (1.526cm)</em>
Replacing:
0.699 = 1.217L mol⁻¹cm⁻¹×C×1.526cm
C = 0.3764 mol/L
<em>Concentration of the solution is 0.376M</em>
The given question is incomplete. The complete question is
The thermite reaction, in which powdered aluminum reacts with iron oxide, is highly exothermic: 
. Use standard enthalpies of formation to find ΔH∘rxn for the thermite reaction. Express the heat of the reaction in kilojoules to four significant figures.
Answer: ΔH∘rxn for the thermite reaction is -851.5 kJ
Explanation:
The balanced chemical reaction is :
We have to calculate the enthalpy of reaction 
.
![\Delta H^o=[n_{Fe}\times \Delta H_f^0_{(Fe)}+n_{Al_2O_3}\times \Delta H_f^0_{(Al_2O_3)}]-[n_{Al}\times \Delta H_f^0_(Al)+n_{Fe_2O_3}\times \Delta H_f^0_{(Fe_2O_3)}]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo%3D%5Bn_%7BFe%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28Fe%29%7D%2Bn_%7BAl_2O_3%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28Al_2O_3%29%7D%5D-%5Bn_%7BAl%7D%5Ctimes%20%5CDelta%20H_f%5E0_%28Al%29%2Bn_%7BFe_2O_3%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28Fe_2O_3%29%7D%5D)
where,
We are given:
Putting values in above equation, we get:
![\Delta H^o_{rxn}=[(2\times 0)+(1\times -1675.5)]-[(2\times 0)+(1\times -824.2)]=-851.5kJ](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B%282%5Ctimes%200%29%2B%281%5Ctimes%20-1675.5%29%5D-%5B%282%5Ctimes%200%29%2B%281%5Ctimes%20-824.2%29%5D%3D-851.5kJ)
ΔH∘rxn for the thermite reaction is -851.5 kJ
<span>An acidic solution has only hydrogen ions and a basic solution has only hydroxide ions </span>statement correctly distinguishes between an acidic and a basic solution
