_ As + _ NaOH → _Na3AsO3 +

How much heat energy, in kilojoules, is required to convert 72.0 gg of ice at −−18.0 ∘C∘C to water at 25.0 ∘C∘C ? Express your a

Ghella [55]

Answer: The enthalpy change is 34.3 kJ

Explanation:

The conversions involved in this process are :

$(1):H_2O(s)(-18^0C)\rightarrow H_2O(s)(0^0C)\\\\(2):H_2O(s)(0^0C)\rightarrow H_2O(l)(0^0C)\\\\(3):H_2O(l)(0^0C)\rightarrow H_2O(l)(25^0C)$

Now we have to calculate the enthalpy change.

$\Delta H=[m\times c_{s}\times (T_{final}-T_{initial})]+n\times \Delta H_{fusion}+[m\times c_{l}\times (T_{final}-T_{initial})]$

where,

$\Delta H$ = enthalpy change = ?

m = mass of water = 72.0 g

$c_{s}$ = specific heat of ice = $2.09J/g^0C$

$c_{l}$ = specific heat of liquid water = $4.184J/g^0C$

n = number of moles of water = $\frac{\text{Mass of water}}{\text{Molar mass of water}}=\frac{72.0g}{18g/mole}=4.00moles$

$\Delta H_{fusion}$ = enthalpy change for fusion = 6010 J/mole

Now put all the given values in the above expression, we get

$\Delta H=[72.0g\times 2.09J/g^0C\times (0-(-18)^0C]+4.00mole\times 6010J/mole+[72.0g\times 4.184J/g^)C\times (25-0)^0C]$ $\Delta H=34279.8J=34.3kJ$ (1 KJ = 1000 J)

Therefore, the enthalpy change is 34.3 kJ

5 0

2 years ago

Continue off my answer

fgiga [73]

Answer:

hshdhdhdhdbdbdbdbdbdbdbddddhddhrhrhrhrhhrdhhdhhhhhbbbbbbbbbbbhhhhhhhhrbbrhrhrbbdbdbddvvdvdvdvdbdbdbdbdbdbfbfhfhdhdhdhdhfhfhdhdgdhdhdhdhdgdhfhdhdhd

4 0

2 years ago

Be sure to answer all parts. part 1 out of 4 how many nucleophilic centers are present in methanol (ch3oh)?

leva [86]

Answer:

One nucleophilic center

Explanation;

Nucleophile:

Nucleophile is a substance which is nucleus loving in nature (<em>Nucleo</em>; Nucleus , <em>phile</em>; Loving). It is known as a specie which donates a lone pair of electrons to electrophile (electron loving) in a chemical reaction.

Thus, Nucleophile is the region of higher electron density in a molecule and attacks on the lower electron density region of another molecule. Also, the nucleophile can also contain a negative charge.

Number of Nucleophilic centers in Methanol:

The chemical structure of Methanol is attached below and it can be observed that the oxygen atom is containing two lone pair of electrons. Hence, the oxygen atom can act as a nucleophilic center. Therefore, there is only one nucleophilic center in methanol.

H₃C-OH + H₃C-Br → H₃C-O-CH₃ + HBr

In above reaction methanol is acting as a nucleophile and is attacking on electrophilic center (Carbon) of methyl bromide yielding dimethyl ether.

8 0

2 years ago

Read 2 more answers

Harvey kept a balloon with a volume of 348 milliliters at 25.0˚C inside a freezer for a night. When he took it out, its new volu

ad-work [718]

Initial volume of the balloon = $V_{1}$ = 348 mL

Initial temperature of the balloon $T_{1}$ = $25.0^{0}C + 273 = 298 K$

Final volume of the balloon $V_{2}$ = 322 mL

Final temperature of the balloon = $T_{2} = ?$

According to Charles law, volume of an ideal gas is directly proportional to the temperature at constant pressure.

$\frac{V_{1} }{T_{1} } =\frac{V_{2} }{T_{2} }$

On plugging in the values,

$\frac{348mL}{298 K} =\frac{322 mL}{T_{2} }$

$T_{2} =276 K$

Therefore, the temperature of the freezer is 276 K

5 0

2 years ago

Convert Au(clo3)2 to s name

Sholpan [36]

Since Au is a symbol for Gold, and once you split the name into to giving each ion its charge... you'll see that this compound has Au+2 and Cl03- .... so the name would be

Gold(II) Chlorate

Hope this helps!

3 0

3 years ago

_ As + _ NaOH → _Na3AsO3 + _H2