Write the electron configuration for Gold

You mix 200. mL of 0.400M HCl with 200. mL of 0.400M NaOH in a coffee cup calorimeter. The temperature of the solution goes from

GuDViN [60]

Answer : The enthalpy of neutralization is, 56.012 kJ/mole

Explanation :

First we have to calculate the moles of HCl and NaOH.

$\text{Moles of HCl}=\text{Concentration of HCl}\times \text{Volume of solution}=0.400mole/L\times 0.200L=0.08mol$

$\text{Moles of NaOH}=\text{Concentration of NaOH}\times \text{Volume of solution}=0.400mole/L\times 0.200L=0.08mol$

The balanced chemical reaction will be,

$HCl+NaOH\rightarrow NaCl+H_2O$

From the balanced reaction we conclude that,

As, 1 mole of HCl neutralizes by 1 mole of NaOH

So, 0.08 mole of HCl neutralizes by 0.08 mole of NaOH

Thus, the number of neutralized moles = 0.08 mole

Now we have to calculate the mass of water.

As we know that the density of water is 1 g/ml. So, the mass of water will be:

The volume of water = $200mL+200L=400mL$

$\text{Mass of water}=\text{Density of water}\times \text{Volume of water}=1g/ml\times 400mL=400g$

Now we have to calculate the heat absorbed during the reaction.

$q=m\times c\times (T_{final}-T_{initial})$

where,

q = heat absorbed = ?

$c$ = specific heat of water = $4.18J/g^oC$

m = mass of water = 400 g

$T_{final}$ = final temperature of water = $27.78^oC=273+25.10=300.78K$

$T_{initial}$ = initial temperature of metal = $25.10^oC=273+27.78=298.1K$

Now put all the given values in the above formula, we get:

$q=400g\times 4.18J/g^oC\times (300.78-298.1)K$

$q=4480.96J$

Thus, the heat released during the neutralization = -4480.96 J

Now we have to calculate the enthalpy of neutralization.

$\Delta H=\frac{q}{n}$

where,

$\Delta H$ = enthalpy of neutralization = ?

q = heat released = -4480.96 J

n = number of moles used in neutralization = 0.08 mole

$\Delta H=\frac{-4480.96J}{0.08mole}=-56012J/mole=-56.012kJ/mol$

The negative sign indicate the heat released during the reaction.

Therefore, the enthalpy of neutralization is, 56.012 kJ/mole

8 0

3 years ago

Which subatomic particles in a negative charge?

Black_prince [1.1K]

The electron is the only subatomic particle that has a negative charge

8 0

3 years ago

The barium isotope 133ba has a half-life of 10.5 years. a sample begins with 1.1×1010 133ba atoms. how many are left after (a) 5

Deffense [45]

Given: Half-life of 133Ba = t1/2 = 10.5 years.

The radio-active materials obeys 1st order dissociation kinetics. Therefore we have:
k = 0.693 / t1/2 = 0.693 / 10.5 = 0.066 years-1.

Also, $k = \frac{2.303}{t} log \frac{Co}{Ct}$
where, Co = initial concentration = 1.1×10^10 atoms
Ct = conc. of Ba at time t.
......................................................................................................................

Answer 1: For t = 5 years
 $0.066 = \frac{2.303}{5} log \frac{Co}{Ct}$
Therefore, $log\frac{Co}{Ct}$ = 0.1432
Therefore, Co/Ct = 1.3908
Therefore, Ct = 7.9086 X 10^9 atoms.

Number of 133Ba atoms left after 5 years = 7.9086 X 10^9.
....................................................................................................................

Answer 2: For t = 30 years
$0.066 = \frac{2.303}{30} log \frac{Co}{Ct}$
Therefore, $log\frac{Co}{Ct}$ = 0.8597
Therefore, Co/Ct = 7.2402
Therefore, Ct = 1.5193 X 10^9 atoms.

Number of 133Ba atoms left after 30 years = 1.5193 X 10^9.
........................................................................................................................

Answer 3: t = 180 years
$0.066 = \frac{2.303}{180} log \frac{Co}{Ct}$
Therefore, $log\frac{Co}{Ct}$ = 5.1585
Therefore, Co/Ct = 1.44 X 10^5
Therefore, Ct = 7.6367 X10^4 atoms.

Number of 133Ba atoms left after 180 years = 7.6367 X10^4.

8 0

4 years ago

Most of the cells in your body right now are in which phase of the cell cycle?

Serga [27]

Answer:ttttttteeeeeeeeehhhhhhhhhhheeeeeeeeeee

Explanation:

3 0

3 years ago

Which structures group together to form a system in the human body

Alexxx [7]

Answer:

organs group together to form organ systems

Explanation:

8 0

3 years ago