Answer:
D. The ionic number.
Explanation:
Whenever an element losses or gains an electron; it becomes charged, thus turns to an ion. The ion can either be positively charged when it losses an electron or negarively charged when it gains an electron. The number shows the required number of electrons gained (negative) or lost (positive).
Answer:
unsaturated fatty acid are liquid in nature, posses multiple bond in it's structure where as saturated fatty acid are solid in nature, have only single bonds in it's structure.
The mass in grams 550 mL of salt water with a density of 1.50 g/cm³ is 825grams.
<h3>DENSITY:</h3>
- The mass of a substance can be calculated by multiplying the density of the substance by its volume. That is;
Mass = density × volume
- According to this question, the volume of the salt is 550mL while its density is given as 1.50g/mL. The mass is calculated as follows:
Mass = 1.50g/mL × 550mL
Mass = 825grams.
Therefore, the mass in grams 550 mL of salt water with a density of 1.50 g/cm³ is 825grams.
Learn more about density at: brainly.com/question/16894337
Answer: The heat required is 6.88 kJ.
Explanation:
The conversions involved in this process are :
Now we have to calculate the enthalpy change.
![\Delta H=[m\times c_{p,s}\times (T_{final}-T_{initial})]+n\times \Delta H_{fusion}+[m\times c_{p,l}\times (T_{final}-T_{initial})]+n\times \Delta H_{vap}+[m\times c_{p,g}\times (T_{final}-T_{initial})]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5Bm%5Ctimes%20c_%7Bp%2Cs%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D%2Bn%5Ctimes%20%5CDelta%20H_%7Bfusion%7D%2B%5Bm%5Ctimes%20c_%7Bp%2Cl%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D%2Bn%5Ctimes%20%5CDelta%20H_%7Bvap%7D%2B%5Bm%5Ctimes%20c_%7Bp%2Cg%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D)
where,
= enthalpy change = ?
m = mass of ethanol = 25.0 g
= specific heat of solid ethanol= 0.97 J/gK
= specific heat of liquid ethanol = 2.31 J/gK
n = number of moles of ethanol = 
= enthalpy change for fusion = 5.02 KJ/mole = 5020 J/mole
= change in temperature
The value of change in temperature always same in Kelvin and degree Celsius.
Now put all the given values in the above expression, we get
![\Delta H=[25.0 g\times 0.97J/gK\times (-114-(-135)K]+0.534mole\times 5020J/mole+[25.0g\times 2.31J/gK\times (-50-(-114))K]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B25.0%20g%5Ctimes%200.97J%2FgK%5Ctimes%20%28-114-%28-135%29K%5D%2B0.534mole%5Ctimes%205020J%2Fmole%2B%5B25.0g%5Ctimes%202.31J%2FgK%5Ctimes%20%28-50-%28-114%29%29K%5D)
(1 KJ = 1000 J)
Therefore, the heat required is 6.88 kJ
Answer:
-490.7 K
Explanation:
Given:
[Ni^2+]= 0.4 M
[Pb^2+]=0.002 M
∆V= -0.012 V
VNi= -0.250V
VPb= -0.126V
F= 96500 C
R= 8.314 JK-1 mol-1
n= 2
From
T= -nF/R [∆V-(VNi-VPb)/ln [Pb2+]/[Ni2+]]
T= 2(96500)/8.314[ (-0.012) -(-0.250) - (-0.126))/ln[0.002]/[0.4]
T= 23213.856(0.112/(-5.298))
T= -490.7 K
