Solve the following: Which one is more metallic

Find the enthalpy of neutralization of HCl and NaOH. 137 cm3 of 2.6 mol dm-3 hydrochloric acid was neutralized by 137 cm3 of 2.6

liraira [26]

Answer : The correct option is, (D) 89.39 KJ/mole

Explanation :

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

$\text{Moles of HCl}=\text{Concentration of HCl}\times \text{Volume of solution}=2.6mole/L\times 0.137L=0.3562mole$

$\text{Moles of NaOH}=\text{Concentration of NaOH}\times \text{Volume of solution}=2.6mole/L\times 0.137L=0.3562mole$

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, 0.3562 mole of HCl neutralizes by 0.3562 mole of NaOH

Thus, the number of neutralized moles = 0.3562 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 = $137ml+137ml=274ml$

$\text{Mass of water}=\text{Density of water}\times \text{Volume of water}=1g/ml\times 274ml=274g$

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 = 274 g

$T_{final}$ = final temperature of water = 325.8 K

$T_{initial}$ = initial temperature of metal = 298 K

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

$q=274g\times 4.18J/g^oC\times (325.8-298)K$

$q=31839.896J=31.84KJ$

Thus, the heat released during the neutralization = -31.84 KJ

Now we have to calculate the enthalpy of neutralization.

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

where,

$\Delta H$ = enthalpy of neutralization = ?

q = heat released = -31.84 KJ

n = number of moles used in neutralization = 0.3562 mole

$\Delta H=\frac{-31.84KJ}{0.3562mole}=-89.39KJ/mole$

The negative sign indicate the heat released during the reaction.

Therefore, the enthalpy of neutralization is, 89.39 KJ/mole

3 0

3 years ago

Which material is a mixture?<br> 1. water<br> 2. air <br> 3. methane<br> 4. magnesium

skelet666 [1.2K]

Pure air is a mixture of several gases that are invisible and odorless. Consists of 78% nitrogen, 21% oxygen, and less than 1% of argon, carbon dioxide.

3 0

3 years ago

Read 2 more answers

You are given a solution that is 518 mM lactose. You need to make up 4.5 L of 16.7 mM solution. What volume do you need to trans

OLga [1]

Answer:

The volume you need to transfer from the stock solution is 0.145 l

Explanation:

Since the number of moles of lactose in the volume of stock solution that you transfer will be the same as the number of moles of lactose in the final solution, you can use this expression:

number of moles in volume to transfer = number of moles in the final solution

Since number of moles = concentration * volume (if the concentration is expressed in molarity), then:

Ci * Vi = Cf * Vf

where:

Ci = concentration of the stock solution.

Vi = volume of the stock solution to be transferred.

Cf = concentration of the final solution

Vf = volume of the final solution

Then, replacing with the data:

518 mM * Vi = 16.7 mM * 4.5 l

Vi = 16.7 mM * 4.5 l / 518 mM

Notice that any concentration unit can be used, as long as the units of the concentration of the stock and final solution are the same.

4 0

3 years ago

What controls the amount of product formed in a chemical reaction

melisa1 [442]

Answer: limiting reactant controls the amount of product formed in a chemical reaction.

* Hopefully this answers your question :) Mark me the brainliest:)

~ 234483279c20~

5 0

3 years ago

If fluorine gas (F₂) occupies a volume of 45.5 L at a pressure of 850

pshichka [43]

Taking into account about the ideal gas law, the mass of fluorine gas is 63.2244 grams.

<h3>What is ideal gas law</h3>

An ideal gas is a theoretical gas that is considered to be composed of randomly moving point particles that do not interact with each other. Gases in general are ideal when they are at high temperatures and low pressures.

The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:

P×V = n×R×T

where:

P is the gas pressure.
V is the volume that occupies.
T is its temperature. The universal constant of ideal gases R has the same value for all gaseous substances.
R is the ideal gas constant.
n is the number of moles of the gas.

<h3>Definition of molar mass</h3>

The molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.

<h3>Mass of fluorine gas</h3>

In this case, you know:

P= 850 mmHg= 1.11842 atm (being 1 mmHg= 0.00131579 atm)
V= 45.5 L
T =100 °C= 373 K (being 0°C= 273 K)
R= 0.082 $\frac{atm L}{mol K}$
n= ?

Replacing in the ideal gas law:

1.11842 atm ×45.5 L = n×0.082 $\frac{atm L}{mol K}$ × 373 K

Solving:

n= (1.11842 atm ×45.5 L)÷ (0.082 $\frac{atm L}{mol K}$ × 373 K)

<u><em>n= 1.6638 moles</em></u>

The molar mass of F₂ is 38 g/mole. Then you can apply the folowing rule of three: If by definition of molar mass 1 mole of the compound contains 38 grams, 1.6638 moles of the compound contains how much mass?

$mass= \frac{1.6638 molesx38 grams}{1 mole}$